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Upcycling of monomers derived from waste polyester plastics via electrocatalysis

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Journal of Energy Chemistry 2025年第2期101卷 535-561页

作者： Haoye Wang Richard Lee Smith Jr Xinhua Qi College of Environmental Science and Engineering Nankai University Graduate School of Environmental studies Tohoku University

Electrocatalysis offers efficient and targeted conversion of monomers derived from waste polyester plastics to chemical products under ambient temperature and pressure *** review provides analysis of research on electrochemical upgrading of monomers derived from waste polyester plastics published from2021 to *** for assessing upgrading of waste polyester plastics include alkaline hydrolysis pretreatment,indices of electrochemical reaction process(activity,stability,and techno-economic a nalysis),separation,and product *** of depolymerization monomers and their value-added products are summarized along with electrocatalytic mechanisms and reaction ***,cathode coupled reactions offer significant value for anodic waste plastic oxidation during electrolysis *** of bifunctional electrocatalysts can reduce the cost of coupled systems and complexity of the *** and recycling of waste plastic monomers using electrocatalytic technology should undergo downstream processing to form high-value products containing C-N and C-S derived functional groups obtained from depolymerized monomers,Electrochemical conversion and upgrading of monomers derived from waste polyester plastics can contribute to industrialization and global economies and help to realize environmental sustainability.

关键词： Coupling reaction Electrocatalysis Monomer Upgrade recycling Value-added products Waste plastics

Chemistry-driven mass spectrometry for structural lipidomics at the C=C bond isomer level

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Chinese Chemical Letters 2025年第1期36卷 225-233页

作者： Junmeng Luo Qiongqiong Wan Suming Chen The Institute for Advanced studies Wuhan UniversityWuhan 430072China

As more and more studies have shown that lipid molecules play an important role in the whole biology,in-depth analysis of lipid structure has become particularly important in *** spectrometry(MS),as the preferred tool for lipid analysis,has greatly promoted the development of this ***,the existing MS methods still face many difficulties in the in-depth or even comprehensive analysis of lipid *** this review,we discuss recent advances in MS methods based on double bond-specific chemistries for the resolving of C=C location and geometry isomers of *** progress has greatly advanced the lipidomics analysis to a deeper structural level and facilitated the development of structural lipid biology.

关键词： Mass spectrometry Structural lipidomics Lipid isomers Double bond location Double bond configuration Chemical derivatization

New Taub-NUT black holes with massive spin-2 hair

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 51-58页

作者： Yu-Qi Chen Hai-Shan Liu Center for Joint Quantum studies and Department of Physics School of ScienceTianjin UniversityTianjin 300350China

We consider Einstein gravity extended with quadratic curvature invariants,within which the well-known Ricci-flat Taub-NUT black hole remains a *** analysis of the unstable Lichnerowicz modes in the Taub-NUT background enables us to identify the mass and NUT parameters(m,n)where new Taub-NUT black holes can *** then adopt numerical techniques to construct these new Taub-NUT black holes,which bifurcate away from the Ricci-flat *** the Ricci-flat Taub-NUT,there can exist two new black holes for an appropriate given temperature,making it a total of three if we include the Ricci-flat one.

关键词： higher derivative gravity black hole solution Taub-NUT spacetime

Liquid metal catalyst for ammonia synthesis at low pressure

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Science China Materials 2025年第2期68卷 681-682页

作者： Ziyue Zeng Chenyang Wang Lei Fu College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China The Institute for Advanced studies Wuhan UniversityWuhan 430072China

Liquid metal(LM)has attracted immense interest as a novel catalyst in the past few years for its distinctive physicochemical properties,encompassing superior electrical and thermal conductivities,as well as exceptional fluidity characteristics at low temperatures[1].In contrast to conventional solid heterogeneous catalysts,the fluidic characteristics of liquid metal catalysts enhance the interaction between catalysts and reactants,boosting mass transfer at the reaction interface.

关键词： catalyst ammonia synthesis

Federated Learning’s Role in Next-Gen TV Ad Optimization

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Computers, Materials & Continua 2025年第1期82卷 675-712页

作者： Gabriela Dobrita Simona-Vasilica Oprea Adela Bâra Department of Economic Informatics and Cybernetics Bucharest University of Economic StudiesBucharest010374Romania

In the rapidly evolving landscape of television advertising,optimizing ad schedules to maximize viewer engagement and revenue has become *** methods often operate in silos,limiting the potential insights gained from broader data analysis due to concerns over privacy and data *** article introduces a novel approach that leverages Federated Learning(FL)to enhance TV ad schedule optimization,combining the strengths of local optimization techniques with the power of global Machine Learning(ML)models to uncover actionable insights without compromising data *** combines linear programming for initial ads scheduling optimization with ML—specifically,a K-Nearest Neighbors(KNN)model—for predicting ad spot *** into account the diversity and the difficulty of the ad-scheduling problem,we propose a prescriptivepredictive approach in which first the position of the ads is optimized(using Google’s OR-Tools CP-SAT)and then the scheduled position of all ads will be the result of the optimization ***,this output becomes the target of a predictive task that predicts the position of new entries based on their characteristics ensuring the implementation of the scheduling at large scale(using KNN,Light Gradient Boosting Machine and Random Forest).Furthermore,we explore the integration of FL to enhance predictive accuracy and strategic insight across different broadcasting networks while preserving data *** FL approach resulted in 8750 ads being precisely matched to their optimal category placements,showcasing an alignment with the intended diversity ***,there was a minimal deviation observed,with 1133 ads positioned within a one-category variance from their ideal placement in the original dataset.

关键词： Ad scheduling prescriptive-predictive approach federated learning KNN

Finite-Time Stability of Impulsive and Switched Hybrid Systems With Delay-Dependent Impulses

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 466-468页

作者： Taixiang Zhang Jinde Cao Mahmoud Abdel-Aty Ardak Kashkynbayev the School of Mathematics Southeast University IEEE the Deanship of Graduate studies and Scientific Research Ahlia University the Jadara Research Center Jadara University the Department of Mathematics Nazarbayev University

Dear Editor,This letter studies finite-time stability (FTS) of impulsive and switched hybrid systems with delay-dependent impulses. Some conditions, based on Lyapunov method, are proposed for ensuring FTS and estimating settling-time function (STF) of the hybrid *** switching dynamics are FTS and impulsive dynamics involve destabilizing delay-dependent impulses, the FTS is retained if the impulses occur infrequently.

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Nickel-catalyzed ligand-controlled switchable skeletal rearrangements:divergent synthesis of isoquinoline-1,3-diones,cyclohexenols,cycloheptenols,and 2-benzazepin-5-ones

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Science China Chemistry 2025年

作者： Yongli Liu Yuanyuan Ping Wangqing Kong The Institute for Advanced studies (IAS) Wuhan University

Skeleton diversity is an important feature of compound libraries and plays a key role in the success of biological ***-controlled divergent synthesis can transform the same substrate into different molecular skeletons, which not only can endow compound libraries with diverse biological activities but also reveal new catalytic modes, and therefore has received extensive attention. Herein, we disclose a Ni-catalyzed, ligand-controlled switchable skeletal rearrangement reaction of acryloyl o-bromobenzamides and activated alkenes. In this protocol, modification of the ligand backbone allows the conversion of the same starting material into four structurally distinct scaffolds of pharmacological importance. Specifically, the use of terpyridine ligand favors the 6-exo cyclization and subsequent 1,2-acyl/Ni dyotropic rearrangement to generate highly functionalized cyclohexenols, while the sterically hinderediPrPDI ligand facilitates the 6-exo cyclization and subsequent 1,2-aryl/Ni dyotropic rearrangement to form highly functionalized cycloheptenols. Furthermore, isoquinoline-1,3-diones were obtained through alkene diarylation in the absence of additional activated alkenes. More strikingly, the bidentate ligand promotes nucleophilic addition of the aryl halides to the amide carbonyl, followed by 1,4-acyl transfer and cross-coupling to afford 2-benzazepin-5-ones.

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Analysis of convective-radiative heat transfer in dovetail longitudinal fins with shape-dependent hybrid nanofluids: a study using the Hermite wavelet method

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Applied Mathematics and Mechanics(English Edition) 2025年第2期46卷 357-372页

作者： C.G.PAVITHRA B.J.GIREESHA S.SUSHMA K.J.GOWTHAM Department of PG studies and Research in Mathematics Kuvempu University

A distinguished category of operational fluids, known as hybrid nanofluids,occupies a prominent role among various fluid types owing to its superior heat transfer properties. By employing a dovetail fin profile, this work investigates the thermal reaction of a dynamic fin system to a hybrid nanofluid with shape-based properties, flowing uniformly at a velocity U. The analysis focuses on four distinct types of nanoparticles,i.e., Al2O3, Ag, carbon nanotube (CNT), and graphene. Specifically, two of these particles exhibit a spherical shape, one possesses a cylindrical form, and the final type adopts a platelet morphology. The investigation delves into the pairing of these *** examination employs a combined approach to assess the constructional and thermal exchange characteristics of the hybrid nanofluid. The fin design, under the specified circumstances, gives rise to the derivation of a differential equation. The given equation is then transformed into a dimensionless form. Notably, the Hermite wavelet method is introduced for the first time to address the challenge posed by a moving fin submerged in a hybrid nanofluid with shape-dependent features. To validate the credibility of this research, the results obtained in this study are systematically compared with the numerical simulations. The examination discloses that the highest heat flux is achieved when combining nanoparticles with spherical and platelet shapes.

关键词： Hermite wavelet method radiation convection dovetail fin nanoparticle configuration O351.2

Tectonic modes of mantle convection and their implications for Earth's tectonic evolution based on three-dimensional numerical simulations

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Science China Earth Sciences 2025年第1期68卷 270-296页

作者： Song XIANG Jinshui HUANG Bingcheng WU School of Earth and Space Sciences University of Science and Technology of ChinaHefei230026China CAS Center of Excellence in Comparative Planetary studies Hefei230026China

Five tectonic modes of mantle convection are obtained and analyzed with three-dimensional numerical models in a spherical shell *** five tectonic convective modes are non-plate mobile-lid,plate-like mobile-lid,episodic plate-like mobile-lid,episodic stagnant-lid,and stagnant-lid convective modes,*** typical characteristics of these five tectonic modes and their numerical classification criteria based on plateness,mobility,and their standard deviations are presented and *** results show that the yield stress of the lithosphere has profound effects on the tectonic convective *** the gradual increase of yield stress,the tectonic mode of mantle convection changes from one to another sequentially through the aforementioned five ***,as the Rayleigh number increases,the range of yield stress for the platelike mobile-lid convective mode decreases,and the dimensionless transition stress between different tectonic modes ***,the dimensional transition stress between the non-plate mobile-lid convective mode and plate-like mobile-lid convective mode increases with the increase of Rayleigh number,but decreases between other tectonic ***,we find that the transition stress between different tectonic modes is inversely proportional to the internal heating rate,with the transition stress decreasing as the internal heating rate *** fitting analysis of the transition stress between tectonic modes shows that Earth's current plate tectonics correspond to a lithospheric yield stress of 150–250 MPa,which aligns with the strength of serpentinized mantle rock determined by experimental *** the Archean mantle was 300℃warmer than it is today,then the Earth was in an episodic stagnant-lid convective *** tectonic evolution of the Earth's surface is closely related to the lithospheric strength and the process of thermal *** the lithospheric strength was only 150 MPa,plate tecton

关键词： Tectonic mode of mantle convection Plate-like mobile-lid convection Episodic plate-like mobile-lid convection Episodic stagnant-lid convection Plate tectonics and tectonic evolution of the Earth