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Co-aromatization of methane and hexane over Pt encapsulated in ZSM-5 zeolite and the electronic effect of K promoters

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Science China Chemistry 2024年第3期67卷 1017-1027页

作者： Bei liu fan wang Xiaomeng Dou Pengfei li Hongwei Xiang Yong Yang Peng He State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China Department of Chemistry Tsinghua UniversityBeijing 100084China National Energy R&D Center for Coal to liquid Fuels Synfuels China Technology Co.Ltd.Beijing 101407China University of Chinese Academy of Sciences Beijing 101408China Leibniz-Institut für Katalyse e.V.an der Universitat Rostock Rostock 18059Germany

The co-aromatization of methane with higher hydrocarbons represents a promising route to valorize methane, an abundant but underexploited carbon resource. In this study, we elucidate a novel approach to enhance the catalytic co-aromatization of hexane and methane by confining Pt within zeolite catalysts and modulating its electron density. Our findings show that encapsulating Pt within MFI structure is pivotal for activating the feedstock and fostering the formation of aromatic products. Interaction between K atoms and the silanol nest forms siloxy groups which are critical for the stabilization of Pt species. Tuning the K content in PtSn@MFI catalysts adeptly alters the electronic configuration of Pt clusters. This modification is corroborated by infrared and X-ray photoelectron spectroscopy analysis, and density functional theory calculations. Remarkably, the catalyst with 0.8 wt% K exhibits an optimal Pt electron density, driving its superior efficacy in the co-aromatization reaction, converting 0.78 mol of methane for each mole of hexane processed. By employing ~(13)C isotopic labeling and solid-state NMR studies, we demonstrate the participation of methane in the adsorbed species inside the zeolite channel and its incorporation to the benzyl site of the substitute group and phenyl rings in aromatic compounds, underscoring the importance of Pt encapsulation.

关键词： Pt encapsulation MFI zeolite methane activation co-aromatization ^(13)C solid-state NMR

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lithiated Graphdiyne Quantum Dots for Stable lithium Metal Anodes

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CCS Chemistry 2024年第5期6卷 1300-1311页

作者： Han Shen Congying Song fan wang Guoxing li Yuliang li Shandong Provincial Key Laboratory for Science of Material Creation and Energy Conversion Science Center for Material Creation and Energy ConversionInstitute of Frontier and Interdisciplinary ScienceShandong UniversityQingdao 266237 Key Laboratory of Organic Solids Institute of ChemistryChinese Academy of SciencesBeijing 100190 University of Chinese Academy of Sciences Beijing 100049

Here,a facile strategy is proposed for the preparation of lithiated graphdiyne quantum dots(GDY-li QDs)with conjugated sp-and sp2-hybridized carbons by the self-assembly technique ofπ–πstacking of lithiated hexaethynylbezene under mild *** as-prepared GDY-li QDs,containing stacked multialkynyl aromatic backbone and abundant lithium(li),show an average diameter of about 2.6 nm and good dispersion in the *** distinctive structures endow GDY-li QDs with superior properties that cannot be matched by traditional QDs,such as strong ion adsorption,li-ion self-concentration,high li-ion conductivity,the nanoconfinement effect,and ion solvation *** from these features,GDY-li QDs can stabilize limetal anodes to effectively suppress li-dendrite growth and significantly improve its li plating/stripping coulombic efficiency(99.3%in the carbonate electrolyte).The full cells with GDY-li QDs protected li-metal anodes,and liNi_(0.8)Co_(0.1)Mn^(0.1)O_(2)cathodes delivered high capacity and excellent cycling stability at high rates,which demonstrates the great potential of GDY-li QDs for application in fast-charging li-metal batteries.

关键词： graphdiyne quantum dots lithiation lithium metal anodes ion distribution

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Superhydrophobic melamine sponge prepared by radiation-induced grafting technology for efficient oil-water separation

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Nuclear Science and Techniques 2024年第9期35卷 103-114页

作者： Ying Sun Wen-Rui wang Dan-Yi li Si-Yi Xu lin lin Man-li Lu Kai fan Chen-Yang Xing lin-fan li Ji-Hao li Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China School of Architecture and Materials Chongqing College of Electronic EngineeringChongqing 401331China Center for Stretchable Electronics and NanoSensors Key Laboratory of Optoelectronic Devices and Systems of Ministry of EducationCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China

This paper presents a superhydrophobic melamine(ME)sponge(ME-g-PLMA)prepared via high-energy radiation-induced in situ covalent grafting of long-alkyl-chain dodecyl methacrylate(LMA)onto an ME sponge for efficient oil–water *** obtained ME-g-PLMA sponge had an excellent pore structure with superhydrophobic(water contact angle of 154°)and superoleophilic *** can absorb various types of oils up to 66–168 times its *** ME-g-PLMA sponge can continuously separate oil slicks in water by connecting a pump or separating oil underwater with a gravity-driven *** addition,it maintained its highly hydrophobic properties even after long-term immersion in different corrosive solutions and repeated oil *** modified ME-g-PLMA sponge exhibited excellent separation properties and potential for oil spill cleanup.

关键词： Radiation-induced graft polymerization Oil–water separation Sponge Superhydrophobic

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Electrically conductive nanowires controlled one pivotal route in energy harvest and microbial corrosion via direct metal-microbe electron transfer

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Journal of Materials Science & Technology 2024年第7期174卷 226-233页

作者： Yuting Jin Jiaqi li Toshiyuki Ueki Borui Zheng Yongqiang fan Chuntian Yang Zhong li Di wang Dake Xu Tingyue Gu Fuhui wang Shenyang National Laboratory for Materials Science Northeastern UniversityShenyang 110819China Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) Northeastern UniversityShenyang 110819China Department of Chemical and Biomolecular Engineering Institute for Corrosion and Multiphase TechnologyOhio UniversityAthensOH 45701USA

Extracellular electron transfer(EET)plays a critical role in bioelectrochemical processes,allowing cou-pling between microorganisms and extracellular solid-state electrodes,metals,or other cells in energy *** studies have suggested a role for outer-surface c-type cytochromes in direct metal-to-microbe electron transfer by Geobacter sulfurreducens,a model electroactive ***,we ex-amined the possibility of other microbially produced electrical contacts by deleting the gene for PilA,the protein monomer that *** assembles into electrically conductive protein nanowires(e-pili).Deleting pilA gene inhibited electron extraction from pure iron and 316L stainless steel up to 31%and 81%,respectively more than deleting the gene for the outer-surface cytochrome *** PilA-deficient phenotype,and the observation that relatively thick biofilms(21.7μm)grew on the metal surfaces at multi-cell distances from the metal surfaces suggest that e-pili contributed significantly to microbial cor-rosion via direct metal-to-microbe electron *** results have implications for the fundamental understanding of electron harvest via e-pili by electroactive microbes,their uses in bioenergy production,as well as in monitoring and mitigation of metal biocorrosion.

关键词： Electrically conductive protein nanowires Direct metal-to-microbe electron transfer Geobacter sulfurreducens Outer-surface c-type cytochromes Biofilm

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Human CD56+CD39+ dNK cells support fetal survival through controlling trophoblastic cell fate:immune mechanisms of recurrent early pregnancy loss

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National Science Review 2024年第6期11卷 129-145页

作者： Wentong Jia liyang Ma Xin Yu Feiyang wang Qian Yang Xiaoye wang Mengjie fan Yan Gu Ran Meng Jian wang Yuxia li Rong li Xuan Shao Yan-ling wang State Key Laboratory of Stem cell and Reproductive Biology Key Laboratory of Organ Regeneration and ReconstructionInstitute of ZoologyChinese Academy of Sciences Beijing Institute for Stem Cell and Regenerative Medicine University of the Chinese Academy of Sciences NHC Key Lab of Reproduction Regulation Shanghai Engineering Research Center of Reproductive Health Drug and Devices Shanghai Institute for Biomedical and Pharmaceutical Technologies National Clinical Center for Obstetrics and Gynecology Peking University Third Hospital Department of Family Planning The Second Hospital of Tianjin Medical University Department of Prenatal Screening Haidian Maternal and Child Health Hospital

Decidual natural killer（dNK） cells are the most abundant immune cells at the maternal-fetal interface during early pregnancy in both mice and humans, and emerging single-cell transcriptomic studies have uncovered various human dNK subsets that are disrupted in patients experiencing recurrent early pregnancy loss（RPL） at early gestational stage, suggesting a connection between abnormal proportions or characteristics of dNK subsets and RPL pathogenesis. However, the functional mechanisms underlying this association remain unclear. Here, we established a mouse model by adoptively transferring human dNK cells into pregnant NOG（NOD/Shi-scid/IL-2Rγnull） mice, where human dNK cells predominantly homed into the uteri of recipients. Using this model, we observed a strong correlation between the properties of human dNK cells and pregnancy outcome. The transfer of dNK cells from RPL patients（dNK-RPL）remarkably worsened early pregnancy loss and impaired placental trophoblast cell differentiation in the recipients. These adverse effects were effectively reversed by transferring CD56+CD39+dNK *** studies revealed that CD56+CD39+dNK subset facilitates early differentiation of mouse trophoblast stem cells（m TSCs） towards both invasive and syncytial pathways through secreting macrophage colony-stimulating factor（M-CSF）. Administration of recombinant M-CSF to NOG mice transferred with dNK-RPL efficiently rescued the exacerbated pregnancy outcomes and fetal/placental development. Collectively, this study established a novel humanized mouse model featuring functional human dNK cells homing into the uteri of recipients and uncovered the pivotal role of M-CSF in fetal-supporting function of CD56+CD39+dNK cells during early pregnancy, highlighting that M-CSF may be a previously unappreciated therapeutic target for intervening RPL.

关键词： recurrent pregnancy loss CD56+CD39+ dNK subset NOG mice adoptive transfer placental trophoblast cell fate M-CSF

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Field experimental study on the effect of thawed depth of frozen alpine meadow soil on rill erosion by snowmelt waterflow

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International Soil and Water Conservation Research 2024年第1期12卷 54-63页

作者： Ying Zheng Xiaonan Shi fan Zhang Tingwu Lei Chen Zeng Xiong Xiao li wang Guanxing wang State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing100101China University of Chinese Academy of Sciences Beijing100101China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing210098China College of Water Resources and Civil Engineering China Agricultural UniversityBeijing100083China College of Geographic Science Hunan Normal UniversityChangsha410081China

Soil erosion by snow or ice melt waterflow is an important type of soil erosion in many high-altitude and high-latitude regions and is further aggravated by climate *** snowmelt waterflow erosion process is affected by soil freeze-thaws and is highly dynamically *** this study,a methodology was developed to conduct in situ field experiments to investigate the effects of the thawed depth of the frozen soil profile on snowmelt waterflow *** method was implemented on an alpine meadow soil slope at an altitude of 3700 m on the northeastern Tibetan *** erosion experiments involved five thawed soil depths of 0,10,30(35),50,and 80(100)mm under two snowmelt waterflow rates(3 and 5 L/min).When the topsoil was fully frozen or shallow-thawed(≤10 mm),its hydrothermal and structural properties caused a significant lag in the initiation of runoff and delayed soil erosion in the initial *** runoff and sediment concentration curves for fully frozen and shallow-thawed soil showed two-stage patterns characteristic of a sediment supply limited in the early stage and subject to hydrodynamic-controlled processes in the later ***,this effect did not exist where the thawed soil depth was greater than 30 *** deep-thawed cases(≥30 mm)showed normal hydrograph and sedigraph patterns similar to those of the unfrozen *** findings of this study are important for understanding the erosion rates of partially thawed soil and for improving erosion simulations in cold regions.

关键词： Snowmelt waterflow erosion Hillslope erosion process Soil freeze and thaw Runoff generation In situ experimental method

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Influences of clean fracturing fluid viscosity and horizontal in-situ stress difference on hydraulic fracture propagation and morphology in coal seam

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International Journal of Coal Science & Technology 2024年第3期11卷 159-175页

作者： Gang wang Shuxin wang Yixin liu Qiming Huang Shengpeng li Shuliang Xie Jinye Zheng Jiuyuan fan College of Safety and Environmental Engineering Shandong University of Science and TechnologyQingdao266590China Mine Disaster Prevention and Control-Ministry of State Key Laboratory Breeding Base Shandong University of Science and TechnologyQingdao266590China

The viscosity of fracturing fluid and in-situ stress difference are the two important factors that affect the hydraulic fracturing pressure and propagation morphology. In this study, raw coal was used to prepare coal samples for experiments, and clean fracturing fluid samples were prepared using CTAB surfactant. A series of hydraulic fracturing tests were conducted with an in-house developed triaxial hydraulic fracturing simulator and the fracturing process was monitored with an acoustic emission instrument to analyze the influences of fracturing fluid viscosity and horizontal in-situ stress difference on coal fracture propagation. The results show that the number of branched fractures decreased, the fracture pattern became simpler, the fractures width increased obviously, and the distribution of AE event points was concentrated with the increase of the fracturing fluid viscosity or the horizontal in-situ stress difference. The acoustic emission energy decreases with the increase of fracturing fluid viscosity and increases with the increase of horizontal in situ stress difference. The low viscosity clean fracturing fluid has strong elasticity and is easy to be compressed into the tip of fractures, resulting in complex fractures. The high viscosity clean fracturing fluids are the opposite. Our experimental results provide a reference and scientific basis for the design and optimization of field hydraulic fracturing parameters.

关键词： Clean fracturing fluid Hydraulic fracturing Viscosity Horizontal in-situ stress difference Hydraulic fracture morphology Acoustic emission

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The Probability Density Function Related to Shallow Cumulus Entrainment Rate and Its Influencing Factors in a Large-Eddy Simulation

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Advances in Atmospheric Sciences 2024年第1期41卷 173-187页

作者： Lei ZHU Chunsong LU Xiaoqi XU Xin HE Junjun li Shi LUO Yuan wang fan wang Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)and Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration Nanjing University of Information Science and TechnologyNanjing 210044China Nanjing Joint Institute for Atmospheric Sciences Nanjing 210019China College of Aviation Meteorology Civil Aviation Flight University of ChinaGuanghan 618307China Collaborative Innovation Center for Western Ecological Safety Lanzhou UniversityLanzhou 730000China Department of Geography Hong Kong Baptist UniversityHong Kong SAR 999077China

The process of entrainment-mixing between cumulus clouds and the ambient air is important for the development of cumulus *** obtaining the entrainment rate(λ)is particularly important for its parameterization within the overall cumulus parameterization *** this study,an improved bulk-plume method is proposed by solving the equations of two conserved variables simultaneously to calculateλof cumulus clouds in a large-eddy *** results demonstrate that the improved bulk-plume method is more reliable than the traditional bulk-plume method,becauseλ,as calculated from the improved method,falls within the range ofλvalues obtained from the traditional method using different conserved *** probability density functions ofλfor all data,different times,and different heights can be well-fitted by a log-normal distribution,which supports the assumed stochastic entrainment process in previous *** analysis demonstrate that the relationship betweenλand the vertical velocity is better than other thermodynamic/dynamical properties;thus,the vertical velocity is recommended as the primary influencing factor for the parameterization ofλin the *** results of this study enhance the theoretical understanding ofλand its influencing factors and shed new light on the development ofλparameterization.

关键词： large-eddy simulation cumulus clouds entrainment rate probability density functions spatial and temporal distribution

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Room-temperature Self-healing and Recyclable PDMS Elastomers with Superior Mechanical Properties for Triboelectric Nanogenerators

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Chinese Journal of Polymer Science 2024年第10期42卷 1566-1577,I0014页

作者： Shu-Juan wang Lu wang Hong-Zhe Su Zhi-Cheng Wu Qiao-Gen Zhang Wei fan Xin-li Jing School of Chemistry Joint Innovation Center of Thermal Protection MaterialsXi’an Jiaotong UniversityXi’an710049China School of Electrical Engineering Xi’an Jiaotong UniversityXi’an710049China School of Textile Science and Engineering Xi’an Polytechnic UniversityXi’an710048China

Polydimethylsiloxane(PDMS)is an electron-withdrawing material that is widely used in triboelectric nanogenerators(TENGs).However,PDMS has poor mechanical properties after curing and is easily damaged when subjected to long-term ***,the long-term stable operation of TENGs under mechanical deformation cannot be *** this work,multiple hydrogen bonds and aromatic disulfide bonds were introduced into PDMS *** elastomers exhibited high toughness(a tensile strength of 1.91 MPa and an elongation at break of 340%),good recyclability,and room-temperature self-healing properties(healing efficiency of 96.4%in 24 h).Recyclable sandwich-like triboelectric nanogenerators with excellent electrical output performance(13.5 V)and room-temperature self-healing performance(24 h,98%recovery of self-generating performance)were prepared by utilizing the hydrogen bonding between the PDMS elastomer and *** work reported herein offers theoretical guidance and a compelling strategy for developing high-performance TENG negative friction layers.

关键词： Polydimethylsiloxane Aromatic disulfide bonds Hydrogen bonds Room temperature self-healing Triboelectric nanogenerator

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Flexible mille-feuille structure electromagnetic interference shielding film with excellent thermal conductivity and Joule heating

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Nano Research 2024年第5期17卷 4544-4554页

作者： Dingwen Yin Huijuan Xiu Simin wang Yanfei Pan Na li Rui Cheng Shaoyan Huang Sha fan Jinbao li College of Bioresources Chemical&Materials Engineering Shaanxi University of Science&TechnologyXi'an 710021China National Demonstration Center for Experimental light Chemistry Engineering Education Shaanxi Provincial Key Laboratory of Papermaking Technology and Specialty Paper DevelopmentXi'an 710021China College of Material Science and Art Design Inner Mongolia Agricultural UniversityHohhot 010018China

The intelligent electronic devices have urgent demands for electromagnetic interference(EMI)shielding films with excellent heat dissipation ***,it is challenging to obtain excellent EMI shielding and thermal conductivity performances ***,inspired by mille-feuille structure,the multifunctional EMI shielding films developed by a layer-by-layer self-assembly and hot-pressing *** ingenious introduction of silver nanoparticles(AgNPs)with large specific surface area and highly conductive into the network formed by TEMPO-oxidized cellulose nanofibrils(TOCNFs)with large aspect ratio to form the TOCNFs/*** the graphene nanoplates(GNPs)with high conductivity loss distributed alternately with TOCNFs/AgNPs to construct mille-feuille structure,which had highly efficient conductive network,complete thermally conduction pathway and rich heterogeneous ***,the designed films presented high electrical conductivity of 8520 S/cm,superb EMI effectiveness(SE)of 98.05 dB,and excellent thermal conductivity of 18.82 W/(m·K).Furthermore,the films possessed outstanding Joule heating performances with low voltages,including high heating temperature(100℃),fast response time(lity and ***,such high-performance EMI shielding films with fascinating thermal conductivity and Joule heating performances have substantial application in flexible electronics,electromagnetic waves shielding and thermal management.

关键词： TEMPO-oxidized cellulose nanofibrils/silver nanoparticles(TOCNFs/AgNPs) mille-feuille structure electromagnetic interference shielding thermal conductivity Joule heating

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