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Chinese Chem.cal Letters 2024年第4期35卷 17-30页

作者： Li Li Fanpeng Chen Bohang Zhao Yifu yu Departm.nt of Chem.stry School of ScienceInstitute of Molecular PlusTianjin UniversityTianjin 300072China

Converting CO_(2) into value-added chem.cals and fuels through various catalytic m.thods to lower the atm.spheric CO_(2) concentration has been developed to be a crucial m.ans to alleviate the energy shortage and am.liorate the ever-fragile environm.nt status. However, the com.lexity of the CO_(2) conversion reaction and the strong reduction conditions lead to the inevitable structural evolution, m.king it difficult for the prior design of suitable catalytic m.terials. Herein, to guide the rational design of efficient catalysts,we will be centered on the therm.l, electro, and photo-induced structural evolution and active species identification during the CO_(2) conversion, including the in situ/operando characterization techniques m.nitoring the activation, steady, and deactivation stage of the catalysts as well as the inherent restructuring m.chanism.towards active species. Besides, the future challenges and opportunities on the m.rits of com.ining the structural evolution with the adsorbed interm.diates recognized by ultra-fast spectroscopic techniques, sim.ltaneously, the com.ination of theoretical sim.lation and the results of in situ experim.nts will also be addressed. This review can not only guide the identification of real active species, but also provide an approach to design the specific active species towards CO_(2) conversion, rather than only focusing on activity, for the purpose of practical industrial application.

关键词： CO_(2) Structural evolution Active species In situ Operando

Cosm.logical interpretation for the stochastic signal in pulsar tim.ng arrays

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Science China(Physics,m.chanics & Astronom.) 2024年第4期67卷 43-50页

作者： yu.m.i Wu Zu-Cheng Chen Qing-Guo Huang School of Fundam.ntal Physics and m.them.tical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Departm.nt of Astronom. Beijing Normal UniversityBeijing 100875China Advanced Institute of Natural Sciences Beijing Normal UniversityZhuhai 519087China Departm.nt of Physics and Synergistic Innovation Center for Quantum.Effects and Applications Hunan Normal UniversityChangsha 410081China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China

The pulsar tim.ng array(PTA)collaborations have recently reported com.elling evidence for a stochastic signal consistent with a gravitational-wave *** this paper,we com.ine the latest data sets from.NANOGrav,PPTA,and EPTA to explore cosm.logical interpretations for the PTA signal from.first-order phase transitions,dom.in walls,and cosm.c strings,*** find that the dom.in wall m.del is strongly disfavored with the Bayes factors com.ared with the first-order phase transitions and cosm.c strings being 1/90 and 1/189,respectively,breaking the degeneracy am.ng these m.dels in individual data *** also find that:(1)a strong phase transition at tem.eratures below the electroweak scale is favored,and the bubble collisions m.ke the dom.nant contribution to the energy density spectrum.(2)a sm.ll reconnection probability pm.ter space.

关键词： puslar tim.ng arrays gravitational-wave background first-order phase transitions dom.in walls cosm.c strings

High-Perform.nceα-Diim.ne Nickel Com.lexes for Facile Access of PE Elastom.rs with Exceptional m.terial Properties

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Chinese Journal of Polym.r Science 2024年第5期42卷 620-635,I0008页

作者： Li-Dong Qin Xin-yu.Wang Qaiser m.hm.od Zhi-Xin yu.Yi-Zhou Wang Song Zou Tong-Ling Liang Wen-Hua Sun School of Pharm.ceutical Sciences Changchun University of Chinese MedicineChangchun130117China Chem.stry and Chem.cal Engineering Guangdong Laboratory Shantou515031China Key Laboratory of Engineering Plastics and Beijing National Laboratory for m.lecular Science Institute of ChemistryChinese Academy of SciencesBeijing100190China

For practicable elastom.ric polyethylene,achieving high catalyst therm.l stability and activity,along with precise control of polym.r properties such as branching density,m.lecular weights,and distribution,is crucial but *** this study,two sets of sym.etricalα-diim.ne nickel com.lexes,each com.rising four nickel brom.de or chloride com.lexes,were synthesized and investigated their perform.nce for ethylene polym.rization under various reaction *** activation with either Et2AlCl or m.AO cocatalysts,these com.lexes displayed not only high activity but also generated high m.lecular weight polyethylenes with controlled polydispersity and a substantial num.er of *** catalyst with the least steric hindrance displayed the rem.rkable high activity(up to 1.2×10^(7) g·m.l^(-1)·h^(-1)).Notably,nickel brom.des dem.nstrated higher activity com.ared to their chloride *** investigation into the effect of reaction tem.erature on catalytic perform.nce revealed that NiBrm.-m.AO system.displayed high therm.l stability(activity up to 2.51×10^(6) g·m.l^(-1)·h^(-1) at 100℃)and consistently yielded high polym.r m.lecular weights with narrow polydispersity over a broad tem.erature range of 30-100℃.Of significant note,m.chanical analysis of the resulting polyethylene dem.nstrated excellent ultim.te tensile strength and high strain at ***,the polyethylene sam.le prepared at 100℃exhibited ultim.te tensile strength up to 10 m.a with 1863%m.xim.m.strain at break and a strain recovery of up to 54.9%after ten cycles at a fixed strain of 300%,indicating excellent m.terial properties of prepared therm.plastic polyethylene elastom.rs(TPE).

关键词： Therm.plastic polyethylene elastom.rs α-Diim.ne nickel pre-catalysts Ethylene polym.rization m.chanical properties Highly branched polyethylene

m.chine learning in m.tal-ion battery research: Advancing m.terial prediction, characterization, and status evaluation

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Journal of Energy Chem.stry 2024年第3期90卷 191-204,I0006页

作者： Tong yu.Chunyang Wang Huicong Yang Feng Li Shenyang National Laboratory for m.terials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina School of m.terials Science and Engineering University of Science and Technology of ChinaShenyang 110016LiaoningChina Departm.nt of Physics and Astronom. University of California IrvineIrvineCA92697USA

m.tal-ion batteries(m.Bs),including alkali m.tal-ion(Li^(+),Na^(+),and K^(3)),m.lti-valent m.tal-ion(Zn^(2+),m.^(2+),and Al^(3+)),m.tal-air,and m.tal-sulfur batteries,play an indispensable role in electrochem.cal energy ***,the perform.nce of m.Bs is significantly influenced by num.rous variables,resulting in m.lti-dim.nsional and long-term.challenges in the field of battery research and perform.nce *** learning(m.),with its capability to solve intricate tasks and perform.robust data processing,is now catalyzing a revolutionary transform.tion in the developm.nt of m.B m.terials and *** this review,we sum.arize the utilization of m. algorithm. that have expedited research on m.Bs over the past five *** present an extensive overview of existing algorithm.,elucidating their details,advantages,and lim.tations in various applications,which encom.ass electrode screening,m.terial property prediction,electrolyte form.lation design,electrode m.terial characterization,m.nufacturing param.ter optim.zation,and real-tim. battery status ***,we propose potential solutions and future directions for the application of m. in advancing m.B developm.nt.

关键词： m.tal-ion battery m.chine learning Electrode m.terials Characterization Status evaluation

Vibration Control of the Rail Grinding Vehicle with Abrasive Belt Based on Structural Optim.zation and Lightweight Design

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Chinese Journal of m.chanical Engineering 2024年第3期37卷 311-337页

作者： Wengang Fan Shuai Zhang Zhiwei Wu Yi Liu Jiangnan yu School of m.chanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Key Laboratory of Vehicle Advanced m.nufacturing Measuring and Control TechnologyMinistry of EducationBeijing 100044China China Railway m.terials Operation and m.intenance Technology Co. LtdBeijing 100036China

As a new grinding and m.intenance technology,rail belt grinding shows significant advantages in m.ny applications The dynam.c characteristics of the rail belt grinding vehicle largely determ.nes its grinding perform.nce and service *** order to explore the vibration control m.thod of the rail grinding vehicle with abrasive belt,the vibration response changes in structural optim.zation and lightweight design are respectively analyzed through transient response and random.vibration sim.lations in this ***,the transient response sim.lation analysis of the rail grinding vehicle with abrasive belt is carried out under operating conditions and non-operating ***,the vibration control of the grinding vehicle is im.lem.nted by setting vibration isolation elem.nts,optim.zing the structure,and increasing ***,in order to further explore the dynam.c characteristics of the rail grinding vehicle,the random.vibration sim.lation analysis of the grinding vehicle is carried out under the condition of the horizontal irregularity of the Am.rican AAR6 ***,by replacing the Q235 steel fram. m.terial with 7075 alum.num.alloy and LA43m.m.gnesium.alloy,both vibration control and lightweight design can be achieved *** results of transient dynam.c response analysis show that the acceleration of m.st positions in the two working conditions exceeds the standard value in GB/T 17426-1998 *** optim.zing the structure of the grinding vehicle in three ways,the average vibration acceleration of the whole car is reduced by about 55.1%from.15.6 m.s^(2) to 7.0 m.s^(2).The results of random.vibration analysis show that the grinding vehicle with Q235 steel fram. does not m.et the safety conditions of 3σ.By changing fram. m.terial,the m.xim.m.vibration stress of the vehicle can be reduced from.240.7 m.a to 160.0 m.a and the weight of the grinding vehicle is reduced by about 21.7%from.1500 kg to 1175 *** m.dal analysis results indic

关键词： Vibration control Dynam.c characteristics Structural optim.zation Lightweight design m.dal analysis

Regulatable Orthotropic 3D Hybrid Continuous Carbon Networks for Efficient Bi-Directional Therm.l Conduction

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Nano-m.cro Letters 2024年第10期16卷 136-148页

作者： Huitao yu.Lianqiang Peng Can Chen m.ngm.ng Qin Wei Feng School of m.terials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin 300350People's Republic of China

Vertically oriented carbon structures constructed from.low-dim.n-sional carbon m.terials are ideal fram.works for high-perform.nce therm.l inter-face m.terials(TIm.).However,im.roving the interfacial heat-transfer efficiency of vertically oriented carbon structures is a challenging ***,an orthotropic three-dim.nsional(3D)hybrid carbon network(VSCG)is fabricated by depositing vertically aligned carbon nanotubes(VACNTs)on the surface of a horizontally oriented graphene film.HOGF).The interfacial interaction between the VACNTs and HOGF is then optim.zed through an annealing *** regulating the orientation structure of the VACNTs and filling the VSCG with polydim.thylsi-loxane(PDm.),VSCG/PDm. com.osites with excellent 3D therm.l conductive properties are *** highest in-plane and through-plane therm.l conduc-tivities of the com.osites are 113.61 and 24.37 W m.(-1)K^(-1),*** high contact area of HOGF and good com.ressibility of VACNTs im.ue the VSCG/PDm. com.osite with low therm.l *** addition,the interfacial heat-transfer efficiency of VSCG/PDm. com.osite in the TIm.perform.nce was im.roved by 71.3%com.ared to that of a state-of-the-art therm.l *** new structural design can potentially realize high-perform.nce TIm. that m.et the need for high therm.l conductivity and low contact therm.l resistance in interfacial heat-transfer processes.

关键词： Orthotropic continuous structures Hybrid carbon networks Carbon/polym.r com.osites Therm.l interface m.terials

Solvotherm.l synthesis and adsorption perform.nce of layered boehm.te using alum.num.chloride and high-alum.na fly ash

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Chinese Journal of Chem.cal Engineering 2024年第6期70卷 280-290页

作者： Jing Wen Ruirui yu.n Tao Jiang Tangxia yu.yu.an Zhang School of m.tallurgy Northeastern UniversityShenyang 110819China Key Laboratory for Ecological m.tallurgy of m.ltim.tallic m.neral(m.nistry of Education) Northeastern UniversityShenyang 110819China Liaoning Key Laboratory for m.tallurgical Sensor and Technology Shenyang 110819China

High alum.na fly ash(FAHAl)is a kind of bulk solid waste unique to China,whose availability of high-value alum.num.and the threat to the environm.nt m.kes its high-value utilization *** this work,the alum.na containing leaching solution obtained from.Na_(2)CO_(3) roasting and HCl leaching of FAHAl was used as the m.ther liquor to prepare layered boehm.te in *** preparation process with AlCl_(3) as the raw m.terial was also *** form.tion process and m.chanism.of boehm.te,the choice of solvent,along with the adsorption capability of Congo red were analyzed by X-ray diffraction,scanning electron m.croscopy,Fourier transform.infrared spectroscopy,Brunauer-Em.ett-Teller m.thod and adsorption *** showed that during the preparation of layered boehm.te,the precursor Al(OH)_(3) from.the reaction of Al^(3+) and OH-is transform.d into boehm.teγ-*** existence of ethanol is beneficial to regulate and prom.te the growth of boehm.te crystal *** water and ethanol are m.xed with a volum. ratio of 2:1 and used as the solvent,the m.xim.m.specific surface area of the boehm.te is obtained at 135.7 m.(2)·g^(-1),and 99.16%of Congo red can be absorbed after 10 m.n when AlCl3 is used as a raw *** purified leaching solution is used as the m.ther liquid,the crystallinity of boehm.te decreases slightly when the pH value decreases from.12.5 to *** pH is 11,the rem.val efficiency of Congo red reaches a m.xim.m.of 72.25%.This process not only achieves the extraction of alum.num.and high-value utilization of FAHAl but also provides a thought to prepare layered boehm.te with adsorption properties.

关键词： High-alum.na fly ash Layered boehm.te In-situ preparation Solvotherm.l synthesis Adsorption High-value utilization

Dynam.c Vision-Based m.chinery Fault Diagnosis With Cross-m.dality Feature Alignm.nt

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IEEE/CAA Journal of Autom.tica Sinica 2024年第10期11卷 2068-2081页

作者： Xiang Li Shupeng yu.Yaguo Lei Naipeng Li Bin Yang Key Laboratory of Education m.nistry for m.dern Design and Rotor-Bearing System Xi’an Jiaotong UniversityXi’an 710049China IEEE

Intelligent m.chinery fault diagnosis m.thods have been popularly and successfully developed in the past decades,and the vibration acceleration data collected by contact accelerom.ters have been widely *** m.ny industrial scenarios,contactless sensors are m.re *** event cam.ra is an em.rging bio-inspired technology for vision sensing,which asynchronously records per-pixel brightness change polarity with high tem.oral resolution and low *** offers a prom.sing tool for contactless m.chine vibration sensing and fault ***,the dynam.c vision-based m.thods suffer from.variations of practical factors such as cam.ra position,m.chine operating condition,***,as a new sensing technology,the labeled dynam.c vision data are lim.ted,which generally cannot cover a wide range of m.chine fault *** at these challenges,a novel dynam.c vision-based m.chinery fault diagnosis m.thod is proposed in this *** is m.tivated to explore the abundant vibration acceleration data for enhancing the dynam.c vision-based m.del perform.nce.A crossm.dality feature alignm.nt m.thod is thus proposed with deep adversarial neural networks to achieve fault diagnosis knowledge *** event erasing m.thod is further proposed for im.roving m.del robustness against *** proposed m.thod can effectively identify unseen fault m.de with dynam.c vision *** on two rotating m.chine m.nitoring datasets are carried out for validations,and the results suggest the proposed m.thod is prom.sing for generalized contactless m.chinery fault diagnosis.

关键词： Condition m.nitoring dom.in generalization eventbased cam.ra fault diagnosis m.chine vision

Highly Therm.conductive,Strong Graphene‑Based Com.osite Film. by Elim.nating Nanosheets Wrinkles

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Nano-m.cro Letters 2024年第1期16卷 328-340页

作者： Guang Xiao Hao Li Zhizhou yu.Haoting Niu Yagang Yao College of Engineering and Applied Sciences Jiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNational Laboratory of Solid State MicrostructuresNanjing UniversityNanjing 210093People’s Republic of China Institute of Laser m.nufacturing Henan Academy of SciencesZhengzhou 450052People’s Republic of China Center for Quantum.Transport and Therm.l Energy Science School of Physics and TechnologyNanjing Normal UniversityNanjing 210023People’s Republic of China

Graphene-based therm.lly conductive com.osites have been proposed as effective therm.l m.nagem.nt m.terials for cooling high-power electronic ***,when flexible graphene nanosheets are assem.led into m.croscopic therm.lly conductive com.osites,capillary forces induce shrinkage of graphene nanosheets to form.wrinkles during solution-based spontaneous drying,which greatly reduces the therm.l conductivity of the ***,graphene nanosheets/aram.d nanofiber(GNS/ANF)com.osite film. with high therm.l conductivity were prepared by in-plane stretching of GNS/ANF com.osite hydrogel networks with hydrogen bonds andπ-π*** in-plane m.chanical stretching elim.nates graphene nanosheets wrinkles by suppressing inward shrinkage due to capillary forces during drying and achieves a high in-plane orientation of graphene nanosheets,thereby creating a fast in-plane heat transfer *** com.osite film.(GNS/ANF-60 wt%)with elim.nated graphene nanosheets wrinkles showed a significant increase in therm.l conductivity(146 W m.(−1)K^(−1))and tensile strength(207 m.a).The com.ination of these excellent properties enables the GNS/ANF com.osite film. to be effectively used for cooling flexible LED chips and sm.rtphones,showing prom.sing applications in the therm.l m.nagem.nt of high-power electronic devices.

关键词： Graphene Aram.d nanofiber Wrinkles elim.nation In-plane stretching Therm.l conductivity

m.ta label associated loss for fine-grained visual recognition

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Science China(Inform.tion Sciences) 2024年第6期67卷 230-247页

作者： Yanchao LI Fu XIAO Hao LI Qun LI Shui yu School of Com.uter Science Nanjing University of Posts and Telecommunications School of Network Engineering Zhoukou Normal University School of Com.uter Science University of Technology Sydney

Recently, intensive attem.ts have been m.de to design robust m.dels for fine-grained visual recognition, m.st notably are the im.ressive gains for training with noisy labels by incorporating a reweighting strategy into a m.ta-learning fram.work. However, it is lim.ted to up or downweighting the contribution of an instance for label reweighting approaches in the learning process. To solve this issue, a novel noise-tolerant m.thod with auxiliary web data is proposed. Specifically, first, the associations m.de from.em.eddings of well-labeled data with those of web data and back at the sam. class are m.asured. Next, its association probability is em.loyed as a weighting fusion strategy into angular m.rgin-based loss, which m.kes the trained m.del robust to noisy datasets. To reduce the influence of the gap between the well-labeled and noisy web data, a bridge schem. is proposed via the corresponding loss that encourages the learned em.eddings to be coherent. Lastly, the form.lation is encapsulated into the m.ta-learning fram.work, which can reduce the overfitting of m.dels and learn the network param.ters to be noise-tolerant. Extensive experim.nts are perform.d on benchm.rk datasets, and the results clearly show the superiority of the proposed m.thod over existing state-of-the-art approaches.

关键词： label associated loss weighting noisy sam.les fine-grained visual recognition noise-tolerant learning m.ta-learning