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A novel metal-free porous covalent organic polymer for efficient room-temperature photocatalytic CO2 reduction via dry-reforming of methane

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Green energy & environment 2024年第9期9卷 1407-1418页

作者： sheng-Yan Yin Ziyi li Yingcai Hu Xiao Luo Jishan li College of Chemistry and Chemical engineering Hunan University Institute of Basic Medicine and Cancer (IBMC) Chinese Academy of Sciences

At room temperature,the conversion of greenhouse gases into valuable chemicals using metal-free catalysts for dry reforming of methane（DRM） is quite promising and ***,we developed a novel covalent organic porous polymer （TPe-COP） with rapid charge separation of the electron–hole pairs for DRM driven by visible light at room temperature,which can efficiently generate syngas （CO and H2）.Both electron donor (tris（4-aminophenyl）amine,TAPA) and acceptor (4,4',4'',4'''-(（1 e,1'e,1''e,1'''e）-(ethene-1,1,2,2-tetrayltetrakis （benzene-4,1-diyl）)tetrakis （ethene-2,1-diyl）)tetrakis (1-（4-formylbenzyl）quinolin-1-ium),TPe-CHO) were existed in TPe-COP,in which the push–pull effect between them promoted the separation of photogenerated electron–hole,thus greatly improving the photocatalytic *** functional theory （DFT） simulation results show that TPe-COP can form charge-separating species under light irradiation,leading to electrons accumulation in TPe-CHO unit and holes in TAPA,and thus efficiently initiating *** 20 h illumination,the photocatalytic results show that the yields reach 1123.6 and 30.8μmol g-1for CO and H2,respectively,which are significantly higher than those of TPe-CHO small *** excellent result is mainly due to the increase of specific surface area,the enhancement of light absorption capacity,and the improvement of photoelectron-generating efficiency after the formation of ***,this work contributes to understanding the advantages of COP materials for photocatalysis and fundamentally pushes metal-free catalysts into the door of DRM field.

关键词： Metal-free Photocatalytic CO 2 reduction Covalent organic polymer Dry-reforming of methane electron donor and acceptor

A CSMA/CA based MAC protocol for hybrid Power-line/Visible-light communication networks:Design and analysis

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Digital Communications and Networks 2024年第2期10卷 481-497页

作者： sheng Hao Huyin Zhang Fei Yang Chenghao li Jing Wang School of Computer Science Central China Normal UniversityWuhan430079PR China Hubei Key Laboratory of intelligent Robot(Wuhan Institute of Technology) Wuhan430079PR China School of Computer Science Wuhan UniversityWuhan430079China School of Information Science and engineering Shandong Normal UniversityJinan250000China School of Computer Science Hubei University of TechnologyWuhan430079China

Hybrid Power-line/Visible-light Communication(HPVC)network has been one of the most promising Cooperative Communication(CC)technologies for constructing Smart Home due to its superior communication reliability and hardware *** research on HPVC networks focuses on the performance analysis and optimization of the Physical(PHY)layer,where the Power line Communication(PLC)component only serves as the backbone to provide power to light emitting Diode(LeD)*** designing a Media Access Control(MAC)protocol remains a great challenge because it allows both PLC and Visible light Communication(VLC)components to operate data transmission,i.e.,to achieve a true HPVC network *** solve this problem,we propose a new HPC network MAC protocol(HPVC MAC)based on Carrier Sense Multiple Access/Collision Avoidance(CSMA/CA)by combining Ieee 802.15.7 and Ieee 1901 ***,we add an Additional Assistance(AA)layer to provide the channel selection strategies for sensor stations,so that they can complete data transmission on the selected channel via the specified CSMA/CA mechanism,*** on this,we give a detailed working principle of the HPVC MAC,followed by the construction of a joint analytical model for mathematicalmathematical validation of the HPVC *** the modeling process,the impacts of PHY layer settings(including channel fading types and additive noise feature),CSMA/CA mechanisms of 802.15.7 and 1901,and practical configurations(such as traffic rate,transit buffer size)are comprehensively taken into ***,we prove the proposed analytical model has the ***,through extensive simulations,we characterize the HPVC MAC performance under different system parameters and verify the correctness of the corresponding analytical model with an average error rate of 4.62%between the simulation and analytical results.

关键词： Hybrid power-line/Visible light communication (HPVC)networks MAC protocol CSMA/CA Ieee 802.15.7 Ieee 1901 Performance analysis

Stochastic uncertain lubrication in gear transmission subjected to tribodynamic loading

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Friction 2024年第8期12卷 1741-1756页

作者： Zhou CHeN Haiming SHA sheng li Zheming TONG Shuiguang TONG State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China School of Mechanical engineering Zhejiang UniversityHangzhou 310027China Wright State University 3640 Colonel Glenn HighwayDaytonOH 45435USA

A stochastic uncertain tribodynamic model is established for a spur gear pair for the first *** stochastic uncertainty of pinion rotation speed propagated to lubrication performance is *** probability density function of the minimum lubricant film thickness hmin evolves over time periodically at interval of an engagement *** between abrupt increase in meshing force and amplification of hmin uncertainty is *** and reliable lubrication performance can be achieved by suppressing the hmin uncertainty and decreasing the lubrication failure *** can be done by increasing lubricant viscosity,and decreasing input torque and uncertainty level of input rotation *** work lays a solid foundation for robust and reliability based optimization for tribodynamic gear system.

关键词： stochastic uncertainty gears elastohydrodynamic lubrication(eHL) tribodynamics

effect of Mo and cold forging deformation on strength and ductility of cobalt-based alloy L605

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Journal of Iron and Steel Research International 2024年第7期31卷 1811-1823页

作者： Zhong-lin Wang Zhi-hua Gong Quan li Han-sheng Bao School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014017Inner MongoliaChina Institute of Special Steels Central Iron and Steel Research Institute Co.Ltd.Beijing 100081China

Mo element was added to cobalt-based alloy L605,and cold forging deformation was *** effects of the addition and cold forging deformation on the microstructure and mechanical properties of the alloy were studied by thermodynamic calculation,electron backscatter diffraction,transmission electron microscopy,and X-ray *** stacking fault energy(SFe)of the alloy decreased after the addition,and the formation of stacking faults and intersections were promoted to improve the strength and *** tensile strength of the alloy with Mo increased from 1190 to 1702 MPa after 24%cold deformation,producing significant work *** strengthening mechanism is strain-induced martensitic transformation(SIMT)and deformation *** alloy,combined with Mo and after 24%deformation,had both high strength and ductility in comparison with the original cobalt-based alloy *** is attributed to the lower SFe which caused the increase in stacking fault *** the tensile process,theε-hcp phase was easily generated at the stacking fault to reduce the stress concentration and increase the *** SIMT by adjusting the density of stacking faults can improve the mechanical properties of cobalt-based ***ε-hcp phase,the interaction between deformation twins and dislocations,and the interaction between e-hcp phases during cold forging deformation caused local stress concentration,lowering ductility and toughness.

关键词： Cobalt-based alloy-Stacking fault energy Strain-induced martensitic transformation Deformation twin Cold forging deformation

Neighbor Sum Distinguishing Total Choosability of Planar Graphs with Maximum Degree at Least 10

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 211-224页

作者： Dong-han Zhang You Lu sheng-gui Zhang li Zhang School of Mathematics and Statistics Northwestern Polytechnical UniversityXi’an710129China School of Mathematics and Computer Application Shangluo UniversityShangluo726000China

A neighbor sum distinguishing(NSD)total coloringφof G is a proper total coloring of G such thatΣz∈eG(u)U{u}φ(z)≠Σz∈eG(v)U{v}φ(z)for each edge uv∈e(G),where eG(u)is the set of edges incident with a vertex *** 2015,Pilśniak and Wozniak conjectured that every graph with maximum degreeΔhas an NSD total(Δ+3)-***,Yang et *** that the conjecture holds for planar graphs withΔ≥10,and Qu et *** that the list version of the conjecture also holds for planar graphs withΔ≥*** this paper,we improve their results and prove that the list version of the conjecture holds for planar graphs withΔ≥10.

关键词： planar graphs neighbor sum distinguishing total choosibility combinatorial nullstellensatz discharging method

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Full sexual maturity-cycle exposure to environmentally relevant concentrations of 17β-estradiol decreases reproductive capacity of zebrafish

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Journal of environmental Sciences 2024年第3期137卷 580-592页

作者： Yongkang Zhang Yuanjun Jiang Qian Sun Meng li sheng Chen Jingyu liang Chunsheng liu College of Fisheries Huazhong Agricultural UniversityWuhan 430070China School of environmental Studies China University of GeosciencesWuhan 430074China

17β-estradiol(e2)has been widely detected in natural water and treatment with e2 induces potential endocrine disrupting effects in ***,effects on fish fecundity and steroid system after treatment with environmentally relevant concentrations of e2 for the full sexual maturation cycle remain *** this study,zebrafish were treatment with 0,10 or100 ng/L e2 from embryo to adult stage,and effects on gonadal development and differentiation,steroid hormone levels,transcription of genes associated with the hypothalamic-pituitary-gonadal-liver(HPG)axis in adults and fertilization rate of offspring were *** results showed that treatment with e2 lead to increased number of feminization in *** females,e2 decreased cumulative amount of spawning and inhibited the maturation of *** males,e2 inhibited the maturation and motility of sperm,as well as decreased the movement speed of *** adverse effects on sperm might be responsible for the reduced fertilization observed in *** addition,treatment with e2 changed the levels of steroid hormones in zebrafish gonad and altered the transcriptional levels of genes associated with HPG axis,which is responsible for the regulation of germ cells maturation and gonadal development in ***,these results suggested that treatment with environmentally relevant concentrations of e2 for the full sexual maturity cycle resulted in adverse effects on reproduction in zebrafish.

关键词： environmental estrogen Zebrafish Fecundity Gonadal development endocrine disruption

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Hierarchical Game Approach for Optimization of Regional Integrated energy System Clusters Considering Bounded Rationality

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CSee Journal of Power and energy Systems 2024年第1期10卷 302-313页

作者： Lei Dong Mengting li Junjie Hu sheng Chen Tao Zhang Xinying Wang Tianjiao Pu school of electrical and electronic engineering North China Electric Power UniversityBeijing 102206China Department of Artificial Intelligence Application Research China Electric Power Research InstituteBeijing 100192China Key Laboratory of Smart Grid of Ministry of education Key Laboratory of Smart Energy&Information Technology of Tianjin MunicipalityTianjin UniversityTianjin 300072China

Regional integrated energy system(RIeS)cluster,i.e.,multi-source integration and multi-region coordination,is an effective approach for increasing energy utilization *** hierarchical architecture and limited information sharing of RIeS cluster make it difficult for traditional game theory to accurately describe their game ***,a hierarchical game approach considering bounded rationality is proposed in this paper to balance the interests of optimizing RIeS cluster under privacy protection.A Stackelberg game with the cluster operator(CO)as the leader and multiple RIeS as followers is developed to simultaneously optimize leader benefit and RIeS utilization ***,a slight altruistic function is introduced to simulate the game behavior of each RIeS agent on whether to cooperate or *** introducing an evolutionary game based on bounded rationality in the lower layer,the flaw of the assumption that participants are completely rational can be ***,for autonomous optimal dispatching,each RIeS is treated as a prosumer,fexibly switching its market participation role to achieve cluster coordination *** studies on a RIeS cluster verify effectiveness of the proposed approach.

关键词： Bounded rationality coordinated optimization evolutionary game regionaIilntegrated energysystem stackelberg game

Metal-metal bonds in Zintl clusters:Synthesis,structure and bonding in[Fe_(2)Sn_(4)Bi_(8)]^(3-)and[Cr_(2)Sb_(12)]^(3-)

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Chinese Chemical Letters 2024年第8期35卷 558-566页

作者： Ya-Nan Yang Zi-sheng li Sourav Mondal Lei Qiao Cui-Cui Wang Wen-Juan Tian Zhong-Ming Sun John e.McGrady State Key Laboratory of element-Organic Chemistry Tianjin Key Lab for Rare Earth Materials and ApplicationsSchool of Materials Science and EngineeringNankai UniversityTianjin 300350China Department of Chemistry University of OxfordInorganic Chemistry LaboratoryOxfordOX13QRUnited Kingdom

We report here the synthesis and characterization of two new members of the M2 e 12 family of endohe-dral Zintl clusters,[Fe_(2)Sn_(4)Bi_(8)]^(3-)and[Cr_(2)Sb_(12)]^(3-),both of which contain open-shell metal dimers encap-sulated inside a triple-decker cluster of main-group *** 75-electron[Fe_(2)Sn_(4)Bi_(8)]^(3-)cluster has a D4h-symmetric structure,while[Cr_(2)Sb_(12)]^(3-),despite having the same 75-electron count,is strongly dis-torted to a geometry that resembles a CrSb_(8)crown capped by a CrSb_(4)*** structural differences between the two are driven by the increasing availability of 3d electron density in the earlier transi-tion metal,which leads,ultimately,to different electronic configurations in the two *** trends precisely mirror those observed in the Me_(10)and Me_(12)families containing a single transition metal ion.

关键词： Zintl anions endohedral clusters Metal-metal bond Second-order Jahn-Teller effect DFT calculation

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energy saving analysis for CO_(2)–O_(2)mixed injection technology in converter steelmaking

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Journal of Iron and Steel Research International 2024年第5期31卷 1095-1103页

作者： Bao-chen Han Chun-liang Gao Ya-qiang li Dan liu Guang-sheng Wei Rong Zhu Hebei Key Laboratory of Material Near-Net Forming Technology School of Material Science and EngineeringHebei University of Science and TechnologyShijiazhuang050018HebeiChina Department of Automotive engineering Hebei Vocational University of Technology and EngineeringXingtai054000HebeiChina School of Metallurgical and ecological engineering University of Science and Technology BeijingBeijing100083China

energy-saving in China's iron and steel industry still relies on the development and improvement of short-term energy saving ***,a special converter smelting technology incorporating energy saving was *** evaluate the energy-saving potential of the CO_(2)–O_(2)mixed injection(COMI)technology,collected production data were used to develop an improved techno-economic *** reveal that the technology can save energy through auxiliary material consumption,sensible heat of solid by-product,iron loss reduction,and energy *** application of COMI technology in an enterprise is cost effective,involving the energy saving potential of 0.206 GJ/t,the cost of conserved energy of−48.83 yuan/GJ,and a simple payback period of 0.35 year for a 60-million-yuan *** analysis shows that the investment cost and discount rate primarily influence the cost of conserved energy of the *** the discount rate increased,the cost of conserved energy also gradually ***,the COMI technology is an energy-saving technology with good development prospects.

关键词： Converter steelmaking COMI technology energy saving Techno-economic model Investment cost