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Efficient epoxidation of propylene over non-noble nickel-based catalyst promoted by alkali metals

Science China Chemistry 2024年第11期67卷 3697-3705页

作者： Wenqian Li Wanting Li Xinxin Cao Longfei Chen Yibo Qin Yanfeng Zhu Yanfei Zhang Gai Miao Lingzhao Kong Jiong Li Xinqing Chen State Key Laboratory of Low carbon Catalysis and carbon dioxide Utilization CAS Key Laboratory of Low-carbon Conversion Science and Engineering Shanghai Advanced Research Institute Chinese Academy of Sciences University of Chinese Academy of Sciences School of Environmental Science and Engineering Suzhou University of Science and Technology Shanghai Synchrotron Radiation Facility Zhangjiang National Lab Shanghai Advanced Research Institute Chinese Academy of Sciences

The application of non-noble metal catalysts in the catalytic direct gas-phase epoxidation of propylene with H2and O2to produce propylene oxide is valuable and challenging. The introduction of alkali metal promoters is one of the effective methods to improve the catalytic activity of catalysts. Herein, a series of alkali metal（Li, Na, K, Rb, and Cs）-promoted Ni/TS-1 catalysts were prepared to deeply understand the effect of alkali metals on the structure-activity relationship for gas-phase epoxidation of propylene. Among them, the Na-Ni/TS-1 catalyst exhibits the highest catalytic activity(propylene conversion of 7.35% and PO formation rate of 157.9 g h-1kgcat-1) and the best stability（long-term stability exceeding 140 h at 200 °C）. X-ray absorption and photoelectron spectroscopy revealed that the electronic structure of Ni can be tuned by the addition of alkali metal ***3-TPD-MS, CO2-TPD-MS, and C3H6-TPD-MS results indicate that the acidity of the catalyst can also be adjusted by the introduction of alkali metal, whereas the Na-Ni/TS-1 catalyst exhibits the strongest C3H6adsorption capacity. Thus, the suitable acid-base properties, unique electronic properties of Ni species, and the strongest propylene adsorption capacity resulted in improved propylene gas-phase epoxidation activity of Na-Ni/TS-1 catalyst. This study not only provides a new strategy for the practical application of nickel-based catalysts in the gas-phase epoxidation of propylene but also provides insights into the promoting effect of alkali metals.

关键词： propylene epoxidation Ni/TS-1 catalyst alkali metal precipitating agents

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An artificial intelligence approach for particle transport velocity prediction in horizontal flows

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Particuology 2024年第9期92卷 234-250页

作者： Haoyu Chen Zhiguo Wang Hai Huang Jun Zhang College of Petroleum Engineering Xi'an Shiyou UniversityXi'an710065China Shaanxi Key Laboratory of carbon dioxide Sequestration and Enhanced Oil Recovery Xi'an710065China College of New Energy Xi'an Shiyou UniversityXi'an710065China Engineering research Center of Smart Energy and carbon Neutral in Oil&Gas Field Universities of Shaanxi ProvinceChina The Erosion/Corrosion research Center The University of TulsaOK74104United States

Particle entrainment is an inevitable phenomenon in pipeline systems,especially during the development and extraction phases of oil and gas *** predicting the critical velocity for particle transport is a key focus for implementing effective sand control *** work presents a semi-supervised learning–deep hybrid kernel extreme learning machine(SSL-DHKELM)model for predicting the critical velocity,which integrates multiple machine learning theories including the deep learning approach,which is adept at advanced feature ***,the SSL framework enhances the model's capabilities when data availability is *** improved slime mould algorithm is also employed to optimize the model's *** proposed model has high accuracy on both the sample dataset and out-of-sample *** trained with only 10%of the data,the model's error still did not increase ***,this model achieves superior predictive accuracy compared to existing mechanistic models,demonstrating its impressive performance and robustness.

关键词： Particle transport Critical velocity Deep learning Semi-supervised learning Extreme learning machine

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A justice and innovative way ahead of consumption-based emission accounting approach

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Science China Earth Sciences 2024年第10期67卷 2999-3010页

作者： Qun SHEN Hongbo DUAN Yun TANG Linbing TANG Li SHANG Xinyu DOU Wei WEI Weiqiang CHEN Zhu LIU State Key Laboratory of Low carbon Catalysis and carbon dioxide Utilization CAS Key Laboratory of Low-Carbon Conversion Science&EngineeringShanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China School of Economics&Management University of Chinese Academy of SciencesBeijing 100190China Key Lab of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Department of Earth System Science Tsinghua UnivesityBeijing 100084China

carbon emission accounting is an important basis for global climate *** on the consumption-based accounting(CBA)method,the characteristics of carbon flow between national,regional,and product processes could be more clearly ***,CBA is more conducive to clarifying the attribution of responsibilities between producers and consumers,with the principles of fairness and *** accounting for carbon emissions in typical countries from 1990 to 2019,we found that the CBA emissions are higher than the production-based accounting(PBA)emissions in major developed countries,while the results are reversed for developing *** the past 30 years,the CBA emissions in targeted developed countries generally have shown a downward trend,while in developing countries,they have shown an upward *** emissions in China have shown a continuous growth trend from 1990 to 2019,but the pace has slowed down significantly over the last ***,the embodied carbon intensity of China’s exports continues to decline,indicating that China is providing more green and low-carbon products to the *** the PV industry as an example,this study further reveals the contribution of specific product industries to the country’s carbon transfer through product carbon footprint *** order to provide a scientific basis for global mitigation and climate governance,it is urgent to innovate a scientific,practical,and standardized CBA technology system.

关键词： Consumption-based accounting Production-based accounting carbon transfer carbon footprint

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Gas diffusion in catalyst layer of flow cell for CO_(2) electroreduction toward C_(2+) products

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Nano research 2024年第3期17卷 1101-1106页

作者： Xiqing Wang Qin Chen Yajiao Zhou Yao Tan Ye Wang Hongmei Li Yu Chen Mahmoud Sayed Ramadan A.Geioushy Nageh K.Allam Junwei Fu Yifei Sun Min Liu Hunan Joint International research Center for carbon dioxide Resource Utilization School of Physics and ElectronicsCentral South UniversityChangsha 410083China School of Energy and Power Engineering Beihang UniversityBeijing 100191China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450002China Central Metallurgical research and Development Institute(CMRDI) P.O.Box 87Helwan 11421CairoEgypt Energy Materials Laboratory School of Sciences and EngineeringThe American University in CairoNew Cairo 11835Egypt research Center for Advanced Energy and carbon Neutrality Beihang UniversityBeijing 100191China

The use of gas diffusion electrode(GDE)based flow cell can realize industrial-scale CO_(2) reduction reactions(CO_(2)RRs).Controlling local CO_(2) and CO intermediate diffusion plays a key role in CO_(2)RR toward multi-carbon(C_(2+))*** this work,local CO_(2) and CO intermediate diffusion through the catalyst layer(CL)was investigated for improving CO_(2)RR toward C_(2+)*** gas permeability tests and finite element simulation results indicated CL can balance the CO_(2) gas diffusion and residence time of the CO intermediate,leading to a sufficient CO concentration with a suitable CO_(2)/H_(2)O supply for high C_(2+)*** a result,an excellent selectivity of C_(2+)products~79%at a high current density of 400 mA·cm^(-2) could be obtained on the optimal 500 nm Cu CL(Cu500).This work provides a new insight into the optimization of CO_(2)/H_(2)O supply and local CO concentration by controlling CL for C_(2+)products in CO_(2)RR flow cell.

关键词： gas diffusion electrode CO_(2)reduction Cu mass transfer C_(2)product

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Thermal properties and high-temperature ablation of high-entropy (Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2) coating on graphite substrate

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Journal of Advanced Ceramics 2024年第8期13卷 1268-1281页

作者： Ana C.Feltrin Daniel Hedman Farid Akhtar division of Materials Science Lulea University of TechnologyLulea 97187Sweden Center for Multidimensional carbon Materials(CMCM) Institute for Basic Science(IBS)Ulsan 44919Republic of Korea

An entropy-stabilized multicomponent ultrahigh-temperature ceramic(UHTC)coating,(Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2),on a graphite substrate was in-situ sintered by spark plasma sintering(SPs)from constituent transition metal diboride ***(Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2) coating had a hardness of 31.2±2.1 GPa and resisted 36.9 GPa of stress before delamination,as observed at the *** temperature-dependent thermal properties of the multicomponent diboride(Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2) were obtained by molecular dynamics(MD)simulations driven by a machine learning force field(MLFF)trained on density functional theory(DFT)*** thermal conductivity,density,heat capacity,and coefficient of thermal expansion obtained by the MD simulations were used in time-dependent thermal stress finite element model(FEM)*** low thermal conductivity(carbon materials in engineering components under extreme environments.

关键词： entropy-stabilized diborides ultrahigh temperature ceramics molecular dynamics(MD)simulations density functional theory(DFT) ablation properties

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Recent research in mechanical properties of geopolymer-based ultrahigh-performance concrete:A review

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Defence Technology（防务技术） 2024年第2期32卷 67-88页

作者： G.Murali division of research&Innovation Uttaranchal UniversityDehradun 248007India

Due to the growing need for sustainable and ultra-high-strength construction materials,scientists have created an innovative ultra-high-performance concrete called Geopolymer based ultra-highperformance concrete(GUHPC).Besides,in the last few decades,there have been a lot of explosions and ballistic attacks around the world,which have killed many civilians and fighters in border *** this context,this article reviews the fresh state and mechanical properties of ***,the ingredients of GUHPC and fresh properties such as setting time and flowability are briefly ***,the review of compressive strength,flexure strength,tensile strength and modulus of elasticity of fibrous ***,the blast and projectile impact resistance performance was ***,the microstructural characteristics were reviewed using the scanning electron microscope and X-ray Powder *** review outcome reveals that the mechanical properties were increased when 30%silica fume was added to a higher dose of steel fibre to improve the microstructure of *** is hypothesized that the brittleness of GUHPC was mitigated by adding 1.5%steel fibre reinforcement,which played a role in the decrease of contact explosion cratering and *** the need for cement in GUHPC was a key factor in the review,indicating a promising potential for lowering carbon ***,GUHPC research is still in its early stages,so more study is required before its full potential can be utilized.

关键词： Mechanical properties Blast Projectile impact Fibre Geopolymer Silica fume Alkaline activators

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Improvement of charge-transfer kinetics via MXene and cobalt containing polyoxometalate loading on CdS for photocatalytic hydrogen production

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Science China Chemistry 2024年

作者： Yu Feng Xiao Fang Jinnuo Zang Bin Song Chunlian Hu Xiaoyu Dong Yong Ding State Key Laboratory of Applied Organic Chemistry Key Laboratory of Advanced Catalysis of Gansu Province College of Chemistry and Chemical Engineering Lanzhou University State Key Laboratory of Low carbon Catalysis and carbon dioxide Utilization State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences

Hydrogen is a renewable and clean energy,and photocatalytic water splitting for hydrogen evolution technology is a promising technical means to solve the development *** this study,the ternary composite Co8POM@MXene–CdS hybrid catalyst was constructed and used for photocatalytic hydrogen *** the condition of AM 1.5G simulated sunlight,the photocatalytic H2evolution rate of the ternary composite was 8.13 mmol g-1h-1,which was more than 25 times higher than that of the bare *** means of synchronous illumination X-ray photoelectron spectroscopy （SI-XPS） and density functional theory （DFT） calculations,it was proved that the loading of MXene and Co8POM improved the photogenerated carrier separation and immigration efficiency on *** photogenerated electrons transfer from CdS to ***8POM containing the{Co4O3}quasi-cubane,as an oxidation co-catalyst,accepts photogenerated holes from CdS to catalyze the oxidation reaction of TEOA,which improves the photocatalytic hydrogen production activity and the stability of CdS.

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Porous poly（triazine-heptazine）s:low-temperature solvothermal synthesis,*HCO intermediate activation and photocatalytic COreduction to CH

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Science China Chemistry 2024年

作者： Zhu Gao Zhiwei Jiang Min Liu Yumin Yang Shahzad Ali Qiujian Xie Yuqiang Li Shuai Gu Younian Liu Juntao Tang Chunyue Pan Jiayin Yuan Guipeng Yu Department of Chemistry and Chemical Engineering Central South University Hunan Joint International research Center for carbon dioxide Resource Utilization School of Physics and ElectronicsCentral South University State Key Laboratory of Superlattices and Microstructures Institute of Semiconductors Chinese Academy of Sciences Department of Materials and Environmental Chemistry Stockholm University

High-temperature ionothermal synthesis has been proven effective in preparing environment-friendly carbon nitride （CN）-based photocatalysts in either triazine or heptazine form for CO2reduction reaction （CO2RR）.However,such a process is usually energy-intensive and suffers from partial carbonization that results in non-porous catalysts and degenerating their ***,we report the preparation of highly porous CN polymers (porous C6N7,C3N3,C4.5N5) through a low-temperature solvothermal polymerization of cyameluric chloride itself or cyanuric chloride itself,or both,*** such,it avoids unfavorable carbonization and allows for fine control of its chemical structure and significantly enlarged surface area (up to669 m2g-1).The pincer-like 2,2′-bipyridine sites of porous C6N7alter the photocatalytic CO2reduction pathways via stabilizing the*HCO intermediates,which promotes further hydrogenation to produce CH4in a high *** from the carbonization-free polymerization,high porosity,and*HCO intermediate activation,porous C6N7gave a superior CO2RR to CH4performance (17.18μmol g-1h-1) as well as high stability （5 successive cycles）,outperforming the bulk and state-of-the-art counterparts of *** opens an avenue for the rational construction of efficient porous CN-based photocatalytic systems,demonstrating their great potential in energy conversion reactions.

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Experimental and computational optimization of Prussian blue analogues as high-performance cathodes for sodium-ion batteries:A review

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Journal of Energy Chemistry 2024年第6期93卷 627-662,I0015页

作者： Gwangeon Oh Junghoon Kim Shivam Kansara Hyokyeong Kang Hun-Gi Jung Yang-Kook Sun Jang-Yeon Hwang Department of Energy Engineering Hanyang UniversitySeoul 04763Republic of Korea Energy Storage research Center Clean Energy Research DivisionKorea Institute of Science and TechnologySeoul 02792Republic of Korea Department of Energy Science Sungkyunkwan UniversitySuwon 16419Republic of Korea KIST-SKKU carbon-Neutral research Center Sungkyunkwan UniversitySuwon 16419Republic of Korea Department of Battery Engineering Hanyang UniversitySeoul 04763Republic of Korea

In this review,we discuss the electrochemical properties of Prussian blue(PB)for Na^(+)storage by combining structural engineering and electrolyte *** integrated experimental data and density functional theory(DFT)in sodium-ion battery(SIB)research to refine the atomic arrangements and crystal lattices and introduce substitutions and *** changes affect the lattice stability,intercalation,electronic and ionic conductivities,and electrochemical *** unraveled the intricate structure-electrochemical behavior relationship by combining experimental data with computational models,including first-principles *** holistic approach identified techniques for optimizing PB and Prussian blue analog(PBA)structu ral properties for *** also discuss the tuning of electrolytes by systematically adjusting their composition,concentration,and additives using a combination of molecular dynamics(MD)simulations and DFT *** review offers a comprehensive assessment of strategies for enhancing the electrochemical properties of PB and PBAs through structural engineering and electrolyte modifications,combining experimental insights with advanced computational simulations,and paving the way for next-generation energy storage systems.

关键词： Prussian blue analogs(PBAs) Sodium ion batteries(SIBs) Structural engineering Electrolyte modifications Experiments Density functional theory(DFT)

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Long cycle-life aqueous Zn battery enabled by facile carbon nanotube coating on Cu current collector

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carbon Energy 2024年第6期6卷 151-164页

作者： Beom-Keun Cho Sung-Ho Huh So Hee Kim Seungho Yu Jong-Seong Bae Jung-Keun Yoo Seung-Ho Yu Department of Chemical and Biological Engineering Korea UniversitySeoulRepublic of Korea Advanced Analysis Center Korea Institute of Science and Technology(KIST)SeoulRepublic of Korea Energy Storage research Center Korea Institute of Science and Technology(KIST)SeoulRepublic of Korea KIST School Division of Energy and Environment TechnologyKorea University of Science and TechnologySeoulRepublic of Korea Busan Center Korea Basic Science Institute(KBSI)BusanRepublic of Korea carbon Composites Department Composites Research DivisionKorea Institute of Materials Science(KIMS)ChangwonRepublic of Korea

As an alternative to Li-ion batteries,aqueous Zn batteries have gained attention due to the abundance of Zn metal,low reduction potential(-0.76 V *** hydrogen electrode),and high theoretical capacity(820 mAh g^(-1))of multivalent Zn2+***,the growth of Zn dendrites and the formation of irreversible surface reaction byproducts pose challenges for ensuring a long battery lifespan and ***,the Cu foil coated with a single-walled carbon nanotube(SWCNT)layer using a facile doctor blade casting method is *** SWCNT-coated Cu foil demonstrates a significantly longer battery lifespan compared to the bare Cu in the half-cell *** operando optical microscopy imaging,we are able to provide intuitive evidence that Zn deposition occurs between the carbon nanotube(CNT)coating and Cu substrate,in agreement with the computational ***,with various imaging techniques,the flat morphology and homogeneous distribution of Zn beneath the SWCNT layer are *** addition,the full-cell using CNT-coated Cu exhibits a long cycle life compared to the control group,thereby demonstrating improved electrochemical performance with limited Zn for the cycling process.

关键词： aqueous Zn battery carbon nanotube operando imaging surface coating

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