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Single-atom photo-catalysts:Synthesis,characterization,and applications

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Nano Materials Science 2024年第3期6卷 284-304页

作者： Siqi Li Ziwang Kan He Wang Jiaxiao Bai Yunyi Liu Song Liu Yingjie Wu College of Chemistry Chemical Engineering and Resource UtilizationNortheast Forestry UniversityHarbin150040China school of Medicine and Health Harbin Institute of TechnologyHarbin150001China

Single-atom catalysts(SACs)are gaining popularity in catalytic reactions due to their nearly 100%atomic utilization and defined active sites,which provide great convenience for studying the catalytic mechanism of ***,SACs still present challenges such as complex formation processes,low loading and easy agglomeration of ***,we systematically discuss the synthesis methods for SACs,including coprecipitation,impregnation,atomic layer deposition,pyrolysis and Anti-Ostwald ripening *** techniques for characterizing single-atom catalysts(SACs)are described in *** utilization of individual atoms in various photocatalytic reactions and their mechanisms of action in different reactions are *** purpose of this review is to introduce single-atom synthesis methods,characterization techniques,specific catalytic action and their applications in the direction of photocatalysis,and to provide a reference for the industrialization of photocatalytic single-atoms,which is currently impossible,in the hope of promoting further development of photocatalytic single-atoms.

关键词： Photocatalysis Single atom Catalytic mechanism

Manipulating Nb-doped SrFeO_(3−δ)with excellent performance for proton-conducting solid oxide fuel cells

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Journal of Advanced Ceramics 2024年第5期13卷 579-589页

作者： Hailu Dai Hongzhe Du Samir Boulfrad Shoufu Yu Lei Bi Qinfang Zhang school of Materials Science and Engineering Yancheng Institute of TechnologyYancheng 224051China College of Science&Engineering Hamad Bin Khalifa UniversityDoha 34110Qatar school of resource Environment and Safety Engineering University of South ChinaHengyang 421001China

Nb-doped SrFeO_(3−δ)(SFO)is used as a cathode in proton-conducting solid oxide fuel cells(H-SOFCs).First-principles calculations show that the SrFe0.9Nb0.1O_(3−δ)(SFNO)cathode has a lower energy barrier in the cathode reaction for H-SOFCs than the Nb-free SrFeO_(3−δ)*** experimental studies show that Nb doping substantially enhances the performance of the SrFeO_(3−δ)***,oxygen vacancies(VO)were introduced into SFNO using the microwave sintering method,further improving the performance of the SFNO *** mechanism behind the performance improvement owing to VO was revealed using first-principles calculations,with further optimization of the SFNO cathode achieved by developing a suitable wet chemical synthesis route to prepare nanosized SFNO *** method significantly reduces the grain size of SFNO compared with the conventional solid-state reaction method,although the solid-state reaction method is generally used for preparing Nb-containing *** a result of defect engineering and synthesis approaches,the SFNO cathode achieved an attractive fuel cell performance,attaining an output of 1764 mW·cm−2 at 700℃ and operating for more than 200 *** manipulation of Nb-doped SrFeO_(3−δ)can be seen as a“one stone,two birds”strategy,enhancing cathode performance while retaining good stability,thus providing an interesting approach for constructing high-performance cathodes for H-SOFCs.

关键词： SrFeO_(3−δ)-(SFO) cathode proton conductor solid oxide fuel cells(SOFCs)

Impacts of proppant distribution on development of tight oil reservoirs with threshold pressure gradient

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Petroleum Science 2024年第1期21卷 445-457页

作者： Ming Yue Wei-Yao Zhu Fei-Fei Gou Tian-Ru Song Yu-Chun You Qi-Tao Zhang State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development Beijing102206China school of Civil and resource Engineering University of Science and Technology BeijingBeijing100083China

Field evidence indicates that proppant distribution and threshold pressure gradient have great impacts on well *** at the development of unconventional oil reservoirs in Triassic Chang-7 Unit,Ordos Basin of China,we presented an integrated workflow to investigate how(1)proppant placement in induced fracture and(2)non-linear flow in reservoir matrix would affect well productivity and fluid flow in the *** with our research before(Yue et al.,2020),here we extended this study into the development of multi-stage fractured horizontal wells(MFHWs)with large-scale complicated fracture *** integrated workflow is based on the finite element method and consists of simulation models for proppant-laden fluid flow,fracture flow,and non-linear seepage flow,*** results indicate that the distribution of proppant inside the induced cracks significantly affects the productivity of the *** we assign an idealized proppant distribution instead of the real distribution,there will be an overestimation of 44.98%in daily oil rate and 30.63%in cumulative oil production after continuous development of 1000 ***,threshold pressure gradient(TPG)also significantly affects the well performance in tight oil *** we simply apply linear Darcy’s law to the reservoir matrix,the overall cumulative oil production can be overrated by 77%after 1000 days of *** general,this research provides new insights into the development of tight oil reservoirs with TPG and meanwhile reveals the significance of proppant distribution and non-linear fluid flow in the production scenario design.

关键词： Proppant distribution Tight oil reservoir Multi-stage fractured horizontal well Threshold pressure gradient Moving boundary

Niduenes A-F,six functionalized sesterterpenoids with a pentacyclic 5/5/5/5/6 skeleton from endophytic fungus Aspergillus nidulans

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Chinese Chemical Letters 2024年第9期35卷 202-205页

作者： Aimin Fu Chunmei Chen Qin Li Nanjin Ding Jiaxin Dong Yu Chen Mengsha Wei Weiguang Sun Hucheng Zhu Yonghui Zhang Hubei Key Laboratory of Natural Medicinal Chemistry and resource Evaluation School of PharmacyTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Niduenes A-F(1-6),six novel sesterterpenoids with unprecedented 5/5/5/5/6 pentacyclic ring skeleton were isolated from endophytic fungus Aspergillus *** 1 and 2 represent the first examples of aromatic pentacyclic *** structures and configurations were elucidated by spectroscopic data and single-crystal X-ray diffraction *** 4 demonstrated potent resensitization of SW620/AD300 cells to paclitaxel(PTX).Rhodamine 123 accumulation assay and docking analysis further support that 4 inhibitory the efflux function of P-glycoprotein(P-gp).

关键词： Aspergillus nidulans Sesterterpenoids Aromatic sesterterpenoids Structure elucidation Single-crystal X-ray diffraction Biosynthetic pathways

Optimized the vanadium electrolyte with sulfate-phosphoric mixed acids to enhance the stable operation at high-temperature

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Frontiers of Chemical Science and Engineering 2024年第2期18卷 13-26页

作者： Ling Ge Tao Liu Yimin Zhang Hong Liu school of resource and Environmental Engineering Wuhan University of Science and TechnologyWuhan 430081China State Environmental Protection Key Laboratory of Mineral Metallurgical resources Utilization and Pollution Control Wuhan University of Science and TechnologyWuhan 430081China Hubei Collaborative Innovation Center for High Efficient Utilization of Vanadium resources Wuhan University of Science and TechnologyWuhan 430081China Hubei Provincial Engineering Technology Research Center of High Efficient Cleaning Utilization for Shale Vanadium resource Wuhan University of Science and TechnologyWuhan 430081China school of resource and Environmental Engineering Wuhan University of TechnologyWuhan 430070China

Herein, the influence of the concentration design and comprehensive performance of the sulfate-phosphoric mixed acid system electrolyte is investigated to realize an electrolyte that maintains high energy density and stable operation at high temperatures. Static stability tests have shown that VOPO4 precipitation occurs only with vanadium(V) electrolyte. The concentration of vanadium ion of 2.0–2.2 mol·L^(–1), phosphoric acid of 0.10–0.15 mol·L^(–1), and sulfuric acid of 2.5–3.0 mol·L^(–1) are suitable for a vanadium redox flow battery in the temperature range from –20 to 50 ℃. The equations for predicting the viscosity and conductivity of electrolytes are obtained by the response surface method. The optimized electrolyte overcomes precipitation generation. It has 2.8 times higher energy density than the non-phosphate electrolyte, and a coulomb efficiency of 94.0% at 50 ℃. The sulfate-phosphoric mixed acid system electrolyte promotes the electrode reaction process, increases the current density, and reduces the resistance. This work systematically optimizes the concentrations of composition of positive and negative vanadium electrolytes with mixed sulfate-phosphoric acid. It provides a basis for the different valence states and comprehensive properties of sulfate-phosphoric mixed acid system vanadium electrolytes under extreme environments, guiding engineering applications.

关键词： all vanadium redox flow battery mixed-acid vanadium electrolyte concentration optimization response surface methodology high-temperature stability

Metal complexes of bipyridine-functionalized covalent organic frameworks as efficient electrocatalysts for oxygen evolution reaction

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Rare Metals 2024年第7期43卷 3096-3106页

作者： Zhuang-Zhuang Wu Tian Xia Ying Liang Yong-Peng Li Zhu-Yin Sui Li-Juan Feng Dao-Xiong Wu Xin-Long Tian Qi Chen State Key Laboratory of Marine resource Utilization in South China Sea School of Marine Science and EngineeringHainan UniversityHaikou 570228China school of Chemistry and Chemical Engineering Yantai UniversityZhuhai519041China school of Bioengineering Zhuhai Campus of Zunyi Medical UniversityZhuhai519041China

Electrocatalytic water splitting is considered a clean and practic al method for producing *** this study,COF-Bpy,a bipyridine-functionalized covalent organic framework(COF),was prepared via post-synthetic modification,after which electrocatalysts for the oxygen evolution reactions(OER)were formed through coordination to single-or double-transition metals(Fe,Co,Ni,FeCo,FeNi or CoNi).COF-Bpy@FeNi delivered the best OER performance among the studied electrocatalysts,with an overpotential of 399 mV at 10 mA·cm^(-2)in an alkaline electrolyte(1.0 mol·L^(-1)KOH aqueous).Notably,the electrocatalytic performance of COF-Bpy@FeNi showed slight degradation during durability testing,which is ascribable to its irreversible benzoquinoline structure and strong metal *** expected,COF-Bpy@FeNi exhibited a low overpotential of 347 mV at a turnover frequency(TOF)of 0.1 s^(-1),which suggests that COF-Bpy@FeNi possesses excellent intrinsic electroc atalytic OER ***,density functional theory(DFT)calculations reveal that the Ni site plays a major role,while the Fe site adjusts the electronic structure of the Ni ions,which rationalizes the excellent OER properties of COF-Bpy@*** study not only provides a simple and efficient method for complexing COFs with transition metals,but also offers a novel strategy for designing porous organic polymer electrocatalysts.

关键词： Covalent organic framework Oxygen evolution reactions(OER)electrocatalyst Nickel-iron synergy Water splitting

Sedimentary characteristics and lithofacies paleogeography of the Cambrian in Sichuan basin, Southwest China

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Petroleum 2024年第2期10卷 224-242页

作者： Lin Xie Xuefei Yang Yanhong Zhang Yan Xu Deming Zeng Ruifeng Tang Yao Du Xingzhi Wang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University school of geoscience and Technology Southwest Petroleum University Schlumberger China S.A. Research Institute of Exploration and Development PetroChina Southwest Oil & Gas Field Company

Cambrian in Sichuan basin developed thick black shale, varies carbonate and clastic rock, which deposited in different sedimentary environment. Sichuan basin in the upper Yangtze platform contained a record of environment during the Cambrian. Detail facies analyses of Cambrian enable us to discuss the sedimentary environment and palaeogeographic setting. Sedimentation commenced in the Early Cambrian with the deposition of shelf facies(Qiongzhusi Formation and Canglangpu Formation). At this stage, thick shale and clastic rock deposited in Sichuan basin. At the end of the Early Cambrian, a carbonate platform developed in upper Yangtze platform, and Sichuan basin was located in restricted platform(Longwangmiao Formation). In the Middle Cambrian, tidal flat and restricted platform developed in Sichuan basin(Douposi Formation), because of continuous regression. During the Late Cambrian,Sichuan basin was located in carbonate platform again(Xixiangchi Formation). There are three types of sedimentary system in the Cambrian of Sichuan basin: clastic sedimentary system, clastics-carbonate mixed sedimentary system and carbonate sedimentary system. Vertically, the basin shows the evolutionary character of clastic-carbonate sedimentary systems. The three sedimentary systems correspond to three “transgression-regression” cycles of the Cambrian. The transgression in the initial period of the Early Cambrian led to the formation of clastic sedimentary system in the Qiongzhusi Formation of Lower Cambrian. The transgression in the later period of the Early Cambrian led to the formation of clasticcarbonate mixed sedimentary system in the Middle-Lower Cambrian. The transgression in the initial period of the Late Cambrian led to the formation of carbonate sedimentary system in the Xixiangchi Formation of Upper Cambrian. With the end of Late Sinian continental rifting ended, Sichuan basin entered a stable evolutionary stage of the craton basin, while the paleo-land developed in the north

关键词： Sichuan basin Cambrian Sedimentary characteristics Lithofacies paleogeography

Highly selective and efficient photocatalytic NO removal:Charge carrier kinetics and interface molecular process

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Nano Research 2024年第3期17卷 1003-1026页

作者： Huan Shang Hongbao Jia Pengpeng Li Hao Li Wenbin Zhang Shuangjun Li Qing Wang Shuning Xiao Ding Wang Guisheng Li Dieqing Zhang school of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China The Education Ministry Key Lab of resource Chemistry Joint International Research Laboratory of Resource Chemistry of Ministry of EducationShanghai Key Laboratory of Rare Earth Functional Materialsand Shanghai Frontiers Science Center of Biomimetic CatalysisShanghai Normal UniversityShanghai 200234China school of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China

The widespread nitrogen oxides(NOx,mainly in NO)in the atmosphere have threatened human health and ecological *** dilute NO(ppb)is difficult to efficiently remove via the traditional process due to its characteristics of low concentration,wide range,large total amount,*** can utilize solar energy to purify NO pollutants under mild conditions,but its application is limited due to the low selectivity of nitrate and poor activity of NO *** underlying reason is that the interface mechanism of NO oxidation is not clearly understood,which leads to the inability to accurately regulate the NO oxidation ***,the recent advances in the photocatalytic oxidation of NO are ***,the common strategies to effectively regulate carrier dynamics such as morphology control,facet engineering,defect engineering,plasma coupling,heterojunction and single-atom catalysts are ***,the progress of enhancing the adsorption and activation of reactants such as NO and O_(2) during NO oxidation is described in detail,and the corresponding NO oxidation mechanisms are ***,the challenges and prospects of photocatalytic NO oxidation are presented in term of nanotechnology for air pollution *** review can shed light on the interface mechanism of NO oxidation and provide illuminating information on designing novel catalysts for efficient NOx control.

关键词： nitrogen oxide(NO)oxidation photocatalysis NO/O_(2)activation charge carrier kinetics interfacial mechanism

Covalent organic frameworks/carbon nanotubes composite with cobalt(II)pyrimidine sites for bifunctional oxygen electrocatalysis

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Nano Materials Science 2024年第4期6卷 419-427页

作者： Zhuangzhuang Wu Lijuan Feng Zhe Lu Xinxin Yu Yuzhen Zhao Junming Luo Shaolei Wang Xinlong Tian Qi Chen State Key Laboratory of Marine resource Utilization in South China Sea School of Marine Science and Engineering Hainan University Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education School of Chemistry Northeast Normal University school of Bioengineering Zhuhai Campus of Zunyi Medical University

With characteristics and advantages of functional composite materials, they are commendably adopted in numerous fields especially in oxygen electrocatalysis, which is due to the significant synergies between various components. Herein, a novel bifunctional oxygen electrocatalyst（Co-CNT@COF-Pyr） has been synthesized through in-situ growth of covalent organic frameworks（COFs） layers on the outer surface of highly conductive carbon nanotubes（CNTs） followed by coordination with Co（II）. For electrocatalytic OER, Co-CNT@COF-Pyr reveals a low overpotential（438 mV） in alkaline electrolyte（1.0 M aqueous solution of KOH） with a current density of 10 mA cm-2, which is comparable to most discovered COF-based catalysts. For electrocatalytic ORR, CoCNT@COF-Pyr exhibits a low H2O2yield range（9.0 %–10.1 %） and a reaction pathway close to 4e-（n =3.82–3.80） in alkaline electrolyte（0.1 M aqueous solution of KOH） within the test potential range of 0.1–0.6 V ***, which is superior to most reported COF-based catalysts. Hence, this research could not only offer an innovative insight into the construction of composites, but also facilitate the practical application of renewable fuel cells, closed water cycle, and rechargeable metal-air batteries.

关键词： Oxygen electrocatalysis Covalent organic frameworks Carbon nanotubes Composite materials