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Confined Mn^(2+) enables effective aerobic oxidation catalysis

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Science China Chemistry 2024年第5期67卷 1545-1553页

作者： Desheng Yuan Sicong ma Xiao Kong Chi Zhang Lin Chen Chengsheng Yang Lihua Wang Zhen Liu Lin Ye Yongmei Liu Rui ma zhi-Pan Liu Yifeng Zhu Yong Cao Xinhe Bao Department of Chemical Physics University of Science and Technology of ChinaHefei 230026China Department of Chemistry Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsCollaborative Innovation Center of Chemistry for Energy MaterialsFudan UniversityShanghai 200438China Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Institute of Advanced Fluorine-Containing materials Zhejiang Normal UniversityJinhua 321004China State Key Laboratory of Catalysis National Laboratory for Clean EnergyCollaborative Innovation Center of Chemistry for Energy MaterialsDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Effective and mild activation of O_(2) is essential but challenging for aerobic oxidation. In heterogeneous catalysis, high-valence manganese oxide(e.g., +4) is known to be active for the oxidation, whereas divalent MnO is ineffective due to its limited capacity to supply surface oxygen and its thermodynamically unstable structure when binding O_(2) in reaction conditions. Inspired by natural enzymes that rely on divalent Mn^(2+), we discovered that confining Mn^(2+) onto the Mn_(2)O_(3) surface through a dedicated calcination process creates highly active catalysts for the aerobic oxidation of 5-hydroxymethylfurfural, benzyl alcohol, and *** Mn_(2)O_(3)-confined Mn^(2+) is undercoordinated and efficiently mediates O_(2) activation, resulting in 2–3 orders of magnitude higher activity than Mn_(2)O_(3) alone. Through low-temperature infrared spectroscopy, we distinguished low-content Mn^(2+) sites at Mn_(2)O_(3) surface, which are difficult to be differentiated by X-ray photoelectron spectroscopy. The combination of in-situ energydispersive X-ray absorption spectroscopy and X-ray diffraction further provides insights into the formation of the newly identified active Mn^(2+) sites. By optimizing the calcination step, we were able to increase the catalytic activity threefold *** finding offers promising frontiers for exploring active oxidation catalysts by utilizing the confinement of Mn^(2+)and oftenignored calcination skills.

关键词： confinement catalysis manganese oxide aerobic oxidation divalent Mn^(2+) operando spectroscopies

MnS–MnO heterogeneous nanocube@N,S-doped carbon as a highly efficient bifunctional water splitting electrocatalyst

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Rare Metals 2024年第5期43卷 1977-1988页

作者： Xue-Qian Wang Xiang-Ying ma Wang-zhi Wu Hui-Bing He Nan-Nan Wang Ren-Ji Zheng Shao-Jian ma Yan-Qiu Zhu Pei-Kang Shen Jin-Liang Zhu School of Resources Environment and MaterialsState Key Laboratory of Featured Metal Materials and Life-Cycle Safety for Composite StructuresCollege of Chemistry and Chemical EngineeringGuangxi UniversityNanning 530004China School of Chemistry and Chemical Engineering Guangxi MinzuUniversity Nanning 530006 China School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China

A stable,efficient,and economical bifunctional electrolytic catalyst would be incredibly beneficial for the development of hydrogen production by electrocatalytic water *** this study,we synthesized a novel MnS–MnO heterogeneous nanocube@N,S-doped carbon(MnS–MnO@NSC).MnS–MnO nanocubes possess rich heterogeneous interfaces and plentiful catalytic active sites to promote electrochemical reactions,while the N,S-doped carbon shell possesses excellent conductivity and catalytic properties and protects the ***–MnO@NSC exhibited excellent electrochemical properties as an effective bifunctional electrocatalyst for the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)in KOH *** the HER,the overpotential was as low as 124 mV at a current density of 10 ma·cm^(-2)while in the OER,it was only 340 mV at 100 ma·cm^(-2)under the same *** addition,a MnS–MnO@NSC||MnS–MnO@NSC electrolyzer exhibited almost comparable activity and higher steadiness than those exhibited by the state-of-the-art Pt/C||RuO_(2)/C system for full water splitting in KOH solution.

关键词： manganese sulfide manganese oxide Doped carbon Heterogeneous nanocube Water splitting

Association between Serum Ferritin Levels and Metabolic-associated Fatty Liver Disease in Adults:a Cross-sectional Study Based on the NHANES

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Current Medical Science 2024年第3期44卷 494-502页

作者： Jiang-hui LI Xue-yao ma Yun YI Lu-rao LI zhi-yong XU Ying CHANG Department of Gastroenterology Zhongnan Hospital of Wuhan UniversityWuhan430071China Hubei Clinical Center and Key Laboratory of Intestinal and Colorectal Diseases Wuhan430071China Endoscopy Center The People’s Hospital of YingshanHuanggang438799China

Objective Ferritin,initially acting as an iron-storage protein,was found to be associated with metabolic *** study was designed to investigate the association between serum ferritin and metabolic-associated fatty liver disease(maFLD)using data from the National Health and Nutrition Examination Survey(NHANES)of the United State of *** A cross-sectional study was conducted,enrolling a total of 2145 participants from the NHANES in the 2017–2018 *** steatosis and liver fibrosis were assessed by ultrasound images and several non-invasive *** regression analysis was conducted to determine the associations between serum ferritin concentration and maFLD and liver *** The analysis revealed that participants with higher serum ferritin levels(Q3 and Q4 groups)had a higher prevalence of maFLD than those with the lowest serum ferritin levels[Q3 vs.Q1:OR=2.17(1.33,3.53),PmaFLD and advanced liver fibrosis in *** serum ferritin levels combined with diabetes are important risk factors for liver fibrosis.

关键词： serum ferritin liver fibrosis metabolic-associated fatty liver disease National Health and Nutrition Examination Survey

Interfacial assembly of 2D polydopamine/graphene heterostructures with well-defined mesopore and tunable thickness for high-energy planar micro-supercapacitors

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Chinese Chemical Letters 2024年第7期35卷 439-444页

作者： Jieqiong Qin zhi Yang Jiaxin ma Liangzhu Zhang Feifei Xing Hongtao Zhang Shuxia Tian Shuanghao Zheng Zhong-Shuai Wu College of Science Henan Agricultural UniversityZhengzhou 450002China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China Mechanical and Electrical Engineering Institute Zhengzhou University of Light IndustryZhengzhou 450002China

Two-dimensional(2D)mesoporous pseudocapacitive polymer/graphene heterostructures combine the advanced merits of 2D materials and mesoporous materials,possessing unique nanosheet structure,large specific surface area(SSA),abundant oxygen/nitrogen-containing groups,desirable electrical conductivity and admirable electrochemical redox activity,and hold great potential for constructing high-performance planar micro-supercapacitors(MSCs).Herein,we demonstrate the interfacial assembly of 2D mesoporous polydopamine/graphene(mPDG)heterostructures with well-defined mesopore structure(12 nm)and adjustable thickness(7.5–14.1 nm)for planar high-energy pseudocapacitive *** to medium thickness,exposed mesopore of 12 nm and large SSA of 108 m^(2)/g,the m PDG with 10.8 nm thickness reveals prominent mass capacitance of 419 F/g and impressive cycling stability with~96%capacitance retention after 5000 ***,the symmetric mPDG-based MSCs with“water-in-salt”gel electrolyte present wide voltage window of 1.6 V,superior volumetric energy density of 11.5 mWh/cm^(3),outstanding flexibility and self-integration ***,this work offers a new platform of controllably synthesizing 2D mesoporous heterostructures for high-performance MSCs.

关键词： 2D materials Mesopores Heterostructures Polydopamine High energy density Micro-supercapacitors

Full waveform inversion based on hybrid gradient

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Petroleum Science 2024年第3期21卷 1660-1670页

作者： Chuang Xie zhi-Liang Qin Jian-Hua Wang Peng Song Heng-Guang Shen Sheng-Qi Yu Ben-Jun ma Xue-Qin Liu Qingdao Innovation and Development Base Harbin Engineering UniversityQingdao266000ShandongChina Qingdao Innovation and Development Center Harbin Engineering UniversityQingdao266000ShandongChina CNOOC Research Institute Co. Ltd.Beijing100028China College of marine Geoscience Ocean University of ChinaQingdao266100ShandongChina Weihai Sunfull Geophysical Exploration Equipment Co. Ltd.Weihai264209ShandongChina

The low-wavenumber components in the gradient of full waveform inversion(FWI)play a vital role in the stability of the ***,when FWI is implemented in some high frequencies and current models are not far away from the real velocity model,an excessive number of low-wavenumber components in the gradient will also reduce the convergence rate and inversion *** solve this problem,this paper firstly derives a formula of scattering angle weighted gradient in FWI,then proposes a hybrid *** hybrid gradient combines the conventional gradient of FWI with the scattering angle weighted gradient in each inversion frequency band based on an empirical formula derived *** weighted hybrid mode,we can retain some low-wavenumber components in the initial lowfrequency inversion to ensure the stability of the inversion,and use more high-wavenumber components in the high-frequency inversion to improve the convergence *** results of synthetic data experiment demonstrate that compared to the conventional FWI,the FWI based on the proposed hybrid gradient can effectively reduce the low-wavenumber components in the gradient under the premise of ensuring inversion *** also greatly enhances the convergence rate and inversion accuracy,especially in the deep part of the *** the field marine seismic data experiment also illustrates that the FWI based on hybrid gradient(HGFWI)has good stability and adaptability.

关键词： Full waveform inversion Hybrid gradient Scattering angle weighted Low-wavenumber component

Active sites and reaction mechanisms of COhydrogenation on zinc-based mixed oxide catalysts

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Science China Chemistry 2024年

作者： Zhuo-Yan Yao Si-Cong ma zhi-Pan Liu Shanghai Key Laboratory of Molecular Catalysis and Innovative materials Key Laboratory of Computational Physical ScienceDepartment of Chemistry Fudan University State Key Laboratory of Metal Organic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai Qi zhi Institution

The conversion of C1 molecules, COx（CO and CO2）, to valuable chemical products has garnered ever-increasing *** many routes, the hydrogenation via thermal catalysis is particularly promising as a key clean energy technology with the increasing supply of green H2. Zinc-based mixed oxide catalysts exhibit exceptional catalytic performance in the COxhydrogenation to value-added hydrocarbons, especially in combination with zeolite. This review overviews the recent achievements in understanding the active sites and reaction mechanisms of COxhydrogenation on zinc-based mixed oxide catalysts, focusing on three most-studied zinc-based mixed oxide catalysts, namely ZnCrOx, ZnAlOxand ZnZrOx. The challenges and future directions are also discussed.

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Leaching behavior and microstructure of phosphorus in converter slag

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Journal of Iron and Steel Research International 2024年第7期31卷 1646-1660页

作者： chao-gang Zhou Jin-yue Li Qing-gong Chen Yin-ye Yang Wei Gong Li-qun Ai Shu-huan Wang Bei-yue ma College of Metallurgy and Energy North China University of Science and TechnologyTangshan 063210HebeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina College of materials Science and Engineering Guizhou Minzu UniversityGuiyang 550025GuizhouChina School of materials and Architectural Engineering Guizhou Normal UniversityGuiyang 550025GuizhouChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina

Converter slag is a by-product of the steelmaking process and contains a large amount of Ca,Fe,P and other *** the phosphorus in the converter slag can be effectively extracted,the resulting phosphorus can be used as a phosphate *** in converter slag is mainly enriched in 2CaO·SiO_(2)-3CaO·P_(2)O_(5)(C_(2)S-C_(3)P)solid solution and is easily dissolved in ***,acid leaching method was used to dissolve the solid solution to extract phosphorus in converter slag,so as to realize the recycling of phosphorus resources in converter *** leaching behavior of three actual converter slags from different steel mills in acid leaching solutions composed of citric acid,sodium hydroxide,hydrochloric acid and deionized water was studied by X-ray diffraction,scanning electron microscopy combined with energy dispersive spectrometry,Fourier transform infrared spectroscopy and Raman spectroscopy to reveal the change in object image structure as well as SiO_(4) and PO_(4) tetrahedron before and after acid *** results show that only a small amount of phosphorus in converter slag with too low basicity is enriched in C_(2)S-C_(3)P solid solution,resulting in poor leaching *** the converter slag has a high basicity,the removal effect of phosphorus is 70.64%-81.88%.In addition,when the basicity of converter slag is roughly the same,the dephosphorization effect of slag with high FeO content is relatively *** acid leaching will cause depolymerization behavior of SiO_(4) and PO_(4) tetrahedron,so that the mole fraction of Q0(Si)(asymmetric stretching vibration of Si-O bond in SiO_(4) tetrahedron with bridge oxygen number of 0)and NBO/Si(non-bridging oxygen in silicate tetrahedra)will ***-containing solids can be obtained from the solution after acid leaching through static precipitation,and the solids have the potential to make phosphate fertilizers.

关键词： Dephosphorization converter slag Acid leaching Phosphorus Solid solution Slag structure

A novel responsive stabilizing Janus nanosilica as a nanoplugging agent in water-based drilling fluids for exploiting hostile shale environments

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Petroleum Science 2024年第2期21卷 1190-1210页

作者： Alain Pierre Tchameni Lv-Yan Zhuo Lesly Dasilva Wandji Djouonkep Robert Dery Nagre Lu-Xin Chen Lin Zhao chao ma Bin-Qiang Xie College of Petroleum Engineering Yangtze UniversityWuhan430100HubeiChina Key Laboratory of Drilling and Production Engineering for Oil and Gas HubeiChina Lost Circulation Control Laboratory National Engineering Laboratory for Petroleum Drilling EngineeringYangtze UniversityWuhan430100HubeiChina College of Petroleum Engineering Shandong Institute of Petroleum and Chemical TechnologyDongying257061ShandongChina Petroleum Engineer Research Institute of Petrochina Dagang Oilfield Tianjin300280China Department of Chemical Engineering Kumasi Technical UniversityP.O.Box 854KumasiGhana

Thermo-responsive nanocomposites have recently emerged as potential nanoplugging agents for shale stabilization in high-temperature water-based drilling fluids(WBDFs). However, their inhibitory properties have not been very effective in high-temperature drilling operations. Thermo-responsive Janus nanocomposites are expected to strongly interact with clay particles from the inward hemisphere of nanomaterials, which drive the establishment of a tighter hydrophobic membrane over the shale surface at the outward hemisphere under geothermal conditions for shale stabilization. This work combines the synergistic benefits of thermo-responsive and zwitterionic nanomaterials to synchronously enhance the chemical inhibitions and plugging performances in shale under harsh conditions. A novel thermoresponsive Janus nanosilica(TRJS) exhibiting zwitterionic character was synthesized, characterized,and assessed as shale stabilizer for WBDFs at high temperatures. Compared to pristine nanosilica(Si NP)and symmetrical thermo-responsive nanosilica(TRS), TRJS exhibited anti-polyelectrolyte behaviour, in which electrolyte ions screened the electrostatic attraction between the charged particles, potentially stabilizing nanomaterial in hostile shaly environments(i.e., up to saturated brine or API brine). macroscopically, TRJS exhibited higher chemical inhibition than Si NP and TRS in brine, prompting a better capability to control pressure penetration. TRJS adsorbed onto the clay surface via chemisorption and hydrogen bonding, and the interactions became substantial in brine, according to the results of electrophoretic mobility, surface wettability, and X-ray diffraction. Thus, contributing to the firm trapping of TRJS into the nanopore structure of the shale, triggering the formation of a tight hydrophobic membrane over the shale surface from the outward hemisphere. The addition of TRJS into WBDF had no deleterious effect on fluid properties after hot-treatment at 190℃, implying that TRJ

关键词： Janus nanosilica Thermo-responsive copolymer Anti-polyelectrolyte effect Shale stabilizer Inhibition Plugging Drilling fluid

High-throughput structure determination of polycrystalline functional materials: a platform for automated 3DED/MicroED data collection

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Science China Chemistry 2024年

作者： Zhenghan Zhang Zhengyin Liang chao ma Cong Lin Jian Li State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical Engineering Nanjing University Department of Mechanical Engineering The Hong Kong Polytechnic University

Structure determination plays the most crucial role in the discovery of novel functional materials, because only by knowing the intrinsic structures can we accurately and completely understand their properties and applications. However, most new materials are obtained in polycrystalline form or even as mixtures with multiple phases when first synthesized, presenting significant challenges in their structure determination and phase elucidation. Fortunately, the developed three-dimensional electron diffraction (3DED/MicroED) has provided a promising solution to overcome these challenges. In this study, we have constructed a state-of-the-art 3DED/MicroED data acquisition equipment by integrating a hybrid-pixel detector with a script developed for SerialEM, and thus successfully developed an automated 3DED/MicroED method for the high-throughput structure determination. To demonstrate its effectiveness, a multiphase sample with complex porous structures is employed, showcasing that individual phases and their structures can be identified and determined, respectively. One remarkable finding is the identification of an impurity metal-organic framework (MOF) that is completely invisible to traditional powder X-ray diffraction in a supposedly “pure” commercial MOF sample. Additionally, our method also enables the atomic-resolution structure determination of flexible covalent organic framework materials, which are highly sensitive to electron beams. Moreover, a new microporous aluminoborate is discovered using this rapid structure determination method. These experimental results highlight the enormous potential of our 3DED/MicroED method in the field of new materials discovery, offering a powerful tool for the structure determination of polycrystalline functional materials.

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