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Science China Chemistry 2022年第11期65卷 2163-2176页

作者： Hongliu Wan nengfeng gong Lichen Liu Department of Chemistry Tsinghua UniversityBeijing 100084China State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China National Energy Center for Coal to Clean Fuels Synfuels China Co.Ltd.Beijing 101407China

Long-chain alkanes are abundant feedstocks supplied by natural resources and chemical industry. Specially, normal long-chain alkanes are primary products from Fischer-Tropsch synthesis(FTS) process, which is an important route for the utilization of coal in China. Facing a shift of energy nexus towards sustainable society, the conversion of long-chain alkanes derived from coal into value-added products(such as alkenes and oxygenates) is of great importance for securing China’s energy supply and the role transition of the commercial FTS plants from fuel makers to chemical suppliers. Among the potential transformation routes,the direct dehydrogenation of long-chain alkanes into alkenes is an attractive and practical route, due to the broad applications of long-chain alkenes(especially the linear α-olefins). In this review, we will summary the key insights obtained from the literature on the dehydrogenation of light alkanes based on supported metal catalysts and the dehydrogenation of alkanes with homogeneous molecular catalysts and then discuss how to translate these lessons into the development of efficient catalysts and processes for the dehydrogenation of long-chain alkanes into long-chain alkenes.

关键词： long-chain alkanes catalytic dehydrogenation α-olefins subnanometric cluster zeolite

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介孔钨铝复合氧化物载铂催化剂催化甘油氢解反应

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南京工业大学学报（自然科学版） 2018年第1期40卷 28-33页

作者：宫能锋陈长林南京工业大学化工学院材料化学工程国家重点实验室江苏南京210009

以Al(OH)_3为铝源,用分步浸渍-焙烧法制备介孔钨铝复合氧化物负载铂催化剂。在连续流动固定床反应器中,考察催化剂催化甘油氢解制备1,3-丙二醇(1,3-PDO)的催化性能与稳定性。通过N2物理吸附、X线衍射(XRD)方法表征反应前后催化剂的结构... 详细信息

以Al(OH)_3为铝源,用分步浸渍-焙烧法制备介孔钨铝复合氧化物负载铂催化剂。在连续流动固定床反应器中,考察催化剂催化甘油氢解制备1,3-丙二醇(1,3-PDO)的催化性能与稳定性。通过N2物理吸附、X线衍射(XRD)方法表征反应前后催化剂的结构。结果表明:介孔钨铝复合氧化物负载铂催化剂的平均孔径为16 nm,催化剂在甘油氢解反应中呈现良好的催化活性。催化剂焙烧温度、反应温度、甘油质量空速(WHSV)及甘油水溶液浓度等因素变化对1,3-丙二醇产率及甘油转化率有较大影响。在160℃、4 MPa、60%甘油水溶液进料、甘油质量空速为0.25 h^(-1)、H_2与甘油摩尔比为100∶1的条件下,介孔钨铝复合氧化物负载铂催化剂催化甘油氢解反应,甘油转化率为54.1%,1,3-丙二醇的产率与选择性分别为26.2%与50.3%。催化剂长期稳定性良好。

关键词：介孔钨铝复合氧化物铂甘油 1,3-丙二醇氢解稳定性

Platinum oxide redefined: a thermally stable two-dimensional crystallineform

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Science China Materials 2025年第2期68卷 683-684页

作者： Bixuan Li Yongji gong Tianmushan Laboratory Hangzhou 310023China School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Catalysis,as a core technology in the chemical industry,plays a pivotal role in numerous fields,including energy,environmental science,and materials ***(Pt),a ubiquitous and indispensable catalyst,has been extensively employed in diverse applications,including industrial chemical transformations and automotive emission control systems[1].However,it was believed to suffer from deactivation under severe operating conditions,particularly in high-temperature and oxidizing *** concept suggests that platinum oxides,decompose or sublimate at elevated temperatures,typically above 700 K[2].Consequently,researchers frequently employ encapsulation techniques for metal particles,utilizing materials such as mesoporous silica[3],zeolites[4],two-dimensional(2D)layered materials[5],and various other protective *** approach necessitates a delicate balance between activity and stability,often resulting in enhanced stability at the expense of catalytic efficiency.

关键词： stability crystalline utilizing

Quantile-based optimization under uncertainties for complex engineering structures using an active learning basis-adaptive PC-Kriging model

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Chinese Journal of Aeronautics 2025年第1期38卷 340-352页

作者： Yulian gong Jianguo ZHANG Dan XU Ying HUANG School of Reliability and Systems Engineering Beihang UniversityBeijing 100191China

The Reliability-Based Design Optimization(RBDO)of complex engineering structures considering uncertainties has problems of being high-dimensional,highly nonlinear,and timeconsuming,which requires a significant amount of sampling simulation *** this paper,a basis-adaptive Polynomial Chaos(PC)-Kriging surrogate model is proposed,in order to relieve the computational burden and enhance the predictive accuracy of a *** active learning basis-adaptive PC-Kriging model is combined with a quantile-based RBDO ***,five engineering cases have been implemented,including a benchmark RBDO problem,three high-dimensional explicit problems,and a high-dimensional implicit *** with Support Vector Regression(SVR),Kriging,and polynomial chaos expansion models,results show that the proposed basis-adaptive PC-Kriging model is more accurate and efficient for RBDO problems of complex engineering structures.

关键词： Reliability-based design optimization Quantile-based Basis-adaptive PC-Kriging Complex engineering structures Active learning Uncertainty

Why do CuAl catalysts outperform in CO_(2) electro-reduction to C_(2)H_(4)?

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Science China Chemistry 2025年第2期68卷 763-771页

作者： Dongfang Cheng gong Zhang Lulu Li Xiangcheng Shi Wenjin Zhu Xintong Yuan Lyudmila Moskaleva Peng Zhang Zhi-Jian Zhao Jinlong gong Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin University Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)Tianjin 300072China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207China Department of Chemistry University of the Free StateBloemfontein 9301South Africa Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China National Industry-Education Platform of Energy Storage Tianjin UniversityTianjin 300350China International Joint Laboratory of Low-carbon Chemical Engineering Tianjin 300192China Tianjin Normal University Tianjin 300387China

Highly efficient CO_(2) electroreduction(CO_(2)RR)holds the promise of closing the carbon ***,the strategies for enhancing activity and selectivity for single C2+ products are still *** paper describes the oxophilicity of doped metals on copper(Cu)as a key descriptor for predicting the selectivity in the production of ethylene and ethanol in CO_(2)*** findings reveal a volcano-like relationship between the*O binding energy and catalytic activity,with aluminum(Al)-doped Cu alloys situated at the *** strong Al–O bond facilitates C–O bond cleavage,thereby promoting C_(2)H_(4) *** grand canonical density functional theory(GCDFT)calculations,we elucidate the significance of strong oxygen affinity in enhancing*CO_(2) adsorption,leading to its activation into a bidentate-adsorbed ***,our results demonstrate that Al doping promotes C–C coupling by altering the adsorption mode of the key intermediate *OCCO,shifting it from a less favorable boattype to a more stable chair-type *** modification significantly contributes to the improved catalytic activity for C2+products on CuAl *** research provides a detailed mechanistic insight into the high activity and selectivity observed in CO_(2)RR to ethylene on CuAl catalysts,underscoring the critical role of metal oxophilicity in enhancing CO_(2)RR performance.

关键词： CO_(2)RR dilute alloy descriptor surface oxophilicity

Dynamic Variation of Vegetation NPP and Its Driving Forces in the Yellow River Basin, China

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Chinese Geographical Science 2025年第1期35卷 24-37页

作者： WANG Shimei MA Yutao gong Jie JIN Tiantian Key Laboratory of Western China’s Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China Center for Remote Sensing of Ecological Environments in Cold and Arid Regions Lanzhou UniversityLanzhou 730000China

The productivity of vegetation is influenced by both climate change and human *** the specific contributions of these influencing factors is crucial for ecological conservation and regional *** study utilized a combination of multi-source data to examine the spatiotemporal patterns of Net Primary Productivity(NPP)in the Yellow River Basin(YRB),China from 1982 to ***,a scenario-based approach was employed to compare Potential NPP(PNPP)with Actual NPP(ANPP)to determine the relative roles of climatic and human factors in NPP *** PNPP was estimated using the Lund-Potsdam-Jena General Ecosystem Simulator(LPJ-GUESS)model,while ANPP was evaluated by the Carnegie-Ames-Stanford Approach(CASA)model using different NDVI data *** model simulations revealed that significant greening occurring in the YRB,with a gradual decrease observed from southeast to *** to the LPJ_GUESS model simulations,areas experiencing an increasing trend in NPP accounted for 86.82% of the *** using GIMMS and MODIS NDVI data with CASA model simulations,areas showing an increasing trend in NPP accounted for 71.42% and 97.02%,***,both climatic conditions and human factors had positive effects on vegetation restoration;approximated 41.15% of restored vegetation areas were influenced by both climate variation and human activities,while around 31.93% were solely affected by climate ***,it was found that human activities served as the principal driving force of vegetation degradation within the YRB,impacting 26.35% of degraded areas solely due to human ***,effective management strategies encompassing both human activities and climate change adaptation are imperative for facilitating vegetation restoration within this *** findings will valuable for enhancing our understanding in NPP changes and its underlying factors,thereby contributing to improved ecological man

关键词： Net Primary Productivity(NPP) vegetation greening Carnegie-Ames-Stanford Approach(CASA) Lund-Potsdam-Jena General Ecosystem Simulator(LPJ_GUESS) Yellow River Basin(YRB),China

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Cross-section design of the flow channels in membrane electrode assembly electrolyzer for CO_(2) reduction reaction through numerical simulations

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Chinese Chemical Letters 2025年第1期36卷 332-337页

作者： Lili Zhang Hui Gao gong Zhang Yuning Dong Kai Huang Zifan Pang Tuo Wang Chunlei Pei Peng Zhang Jinlong gong Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China National Industry-Education Platform of Energy Storage Tianjin UniversityTianjin 300350China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207China

Membrane electrode assembly(MEA)is widely considered to be the most promising type of electrolyzer for the practical application of electrochemical CO_(2) reduction reaction(CO_(2)RR).In MEAs,a square-shaped cross-section in the flow channel is normally adopted,the configuration optimization of which could potentially enhance the performance of the *** paper describes the numerical simulation study on the impact of the flow-channel cross-section shapes in the MEA electrolyzer for CO_(2)*** results show that wide flow channels with low heights are beneficial to the CO_(2)RR by providing a uniform flow field of CO_(2),especially at high current ***,the larger the electrolyzer,the more significant the effect *** study provides a theoretical basis for the design of high-performance MEA electrolyzers for CO_(2)RR.

关键词： Electrochemical reduction of CO_(2) Membrane electrode assembly Mass transfer Gas diffusion electrode Computational fluid dynamics

Gas-Solid Flow,Combustion Characteristics,and Gas Emissions in a 75 t/h CFB Boiler Based on the CPFD Method

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Journal of Thermal Science 2025年第1期34卷 323-336页

作者： HUANG Xiankun BAI Zhang ZHU Xiaoli WANG Shuoshuo MU Lin gong Liang College of New Energy China University of Petroleum(East China)Qingdao 266580China Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education School of Energy and Power EngineeringDalian University of TechnologyDalian 116024China

A 3D simulation using Computational Particle Fluid Dynamics(CPFD)methods was used to calculate coal combustion in a 75 t/h industrial-scale circulating fluidized bed(CFB)*** characteristics,gas-solid flow characteristics,and gaseous pollutant emissions of CFB boilers from combustion ignition to stable operation were systematically evaluated in this *** show that the temperature distribution is relatively uniform throughout the *** the combustion process unfolds within the boiler,the gas composition curve strikingly portrays the inverse correlation between CO_(2)and O_(2)*** the combustion reaction progresses,it becomes evident that the concentration of CO_(2)progressively increases,while the concentration of O_(2)concurrently *** inverse relationship underscores the fundamental combustion reaction,where carbon-based fuels react with oxygen to produce carbon dioxide and release ***,a comprehensive analysis has revealed that,from ignition to stable combustion,both nitric oxide(NO)and sulfur dioxide(SO_(2))emissions exhibit a declining *** reduction in pollutant generation is attributed to the improvement in combustion *** complete combustion leads to lower levels of unburned hydrocarbons,which are prone to NO ***,the sulfur content in the fuel is more efficiently oxidized to sulfur trioxide(SO_(3))or bound in sulfates,reducing SO_(2)*** steady state in the simulation,the SO_(2)mass flow rate varies significantly with the furnace height,gradually increasing from 0.07 kg·s^(-1)at 4 m at the bottom of the furnace to a peak of 0.078 kg·s^(-1)at 8 m in the center,and then decreasing to 0.06 kg·s^(-1)at 20m at the top of the furnace.

关键词： circulating fluidized bed particle flow combustion CPFD modeling

Reconstruction characteristics of gut microbiota from patients with type 1 diabetes affect the phenotypic reproducibility of glucose metabolism in mice

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Science China(Life Sciences) 2025年第1期68卷 176-188页

作者： Zhiyi Wang Mengxue gong Yuanyuan Fang Huijuan Yuan Chenhong Zhang State Key Laboratory of Microbial Metabolism School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghai 200240China Department of Endocrinology Henan Provincial People’s HospitalPeople’s Hospital of Zhengzhou UniversityZhengzhou 450003China

The human microbiota-associated(HMA)mice model,especially the germ-free(GF)-humanized mice,has been widely used to probe the causal relationships between gut microbiota and human diseases such as type 1 diabetes(T1D).However,most studies have not clarified the extent to which the reconstruction of the human donor microbiota in recipient mice correlates with corresponding phenotypic *** this study,we transplanted fecal microbiota from five patients with T1D and four healthy people into GF mice,and microbiota from each donor were transplanted into 10 *** with similar microbiota structure to the donor exhibited better phenotypic *** characteristics of the microbial community assembly of donors also influenced the phenotypic reproducibility in mice,and individuals with a higher proportion of stochastic processes showed more severe *** enriched in patients with T1D had a stronger colonization potential in mice with impaired glucose metabolism,and microbiota functional features related to T1D were better reproduced in these *** indicates that assembly traits and colonization efficacy of microbiota influence phenotypic reproducibility in GF-humanized *** findings provide important insights for using HMA mice models to explore links between gut microbiota and human diseases.

关键词： gut microbiome human microbiota-associated animal model type 1 diabetes

Methyl Groups Pendant on Triphenylmethane Toward Modulating Thermal Stability and Dielectric Properties of the Crosslinkable Fluorinated Polyimide Films with High Transparency

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Chinese Journal of Polymer Science 2025年第2期43卷 316-327页

作者： Wen Yang Liang Yuan Kai gong Ruo-Han Zhang Lan Lei Hui Li School of Chemistry and Chemical Engineering Shandong Key Laboratory of Fluorine Chemistry and Chemical Engineering MaterialsUniversity of JinanJinan250022China School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin300350China

It is urgent to develop high-performance polyimide(PI)films that simultaneously exhibit high transparency,exceptional thermal stability,mechanical robustness,and low dielectric to fulfil the requirements of flexible display ***,a series of fluorinated polyimide films(FPIs)were fabricated by the condensation of 5,5′-(perfluoropropane-2,2-diyl)bis(isobenzofuran-1,3-dione)(6FDA)and the fluorinated triphenylmethane diamine monomer(EDA,MEDA and DMEDA)with heat-crosslinkable tetrafluorostyrene side groups,which was incorporated by different numbers of methyl groups pendant in the ortho position of amino ***,the FPI films underwent heating to produce crosslinking FPIs(C-FPIs)through the self-crosslinking of double bonds in the *** transparency,solvent resistance,thermal stability,mechanical robustness and dielectric properties of FPI and C-FPI films can be tuned by the number of methyl groups and crosslinking,which were deeply investigated by virtue of molecular dynamics(MD)simulations and density functional theory(DFT).As a result,all the films exhibited exceptional optically colorless and transparent,with transmittance in the visible region of 450-700 nm exceeding 79.9%,and the cut-off wavelengths(λ_(off))were nearly 350 *** thermal decomposition temperatures at 5% weight loss(T_(d5%))for all samples exceeded 504℃.These films exhibited a wide range of tunable tensile strength(46.5-75.1 MPa).Significantly,they showed exceptional dielectric properties with the dielectric constant of 2.3-2.5 at full frequency(10^(7)-20 Hz).This study not only highlights the relationship between the polymer molecular structure and properties,but offer insights for balancing optical transparency,heat resistance and low dielectric constant in PI films.

关键词： Crosslinkable fluorinated polyimide Methyl group Triphenylmethane Transparency Thermal stability Low dielectric constant