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Dynamical complexity of Anosov systems driven by a quasi-periodic force

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Science China Mathematics 2025年第1期 89-136页

作者： Wen huang zeng Lian Kening Lu Department of Mathematics University of Science and Technology of China School of Mathematics Sichuan University

Consider C2Anosov systems on a compact manifold driven by a quasi-periodic *** study their dynamical complexity on various levels from the perspectives of both path-wise dynamics and stochastic *** that these systems are non-wandering（i.e.,every point in the phase space is nonwandering）,we prove a set of results:（1） the existence of abundance of random periodic points;（2） a random Liv?ic theorem;（3） a random Ma?é-Bousch-Conze-Guivarc'h lemma;（4） the existence of strong random ***,a concrete example constructed on a 2-dimensional torus is also given to uncover some interesting phenomena of the systems.

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Copper-catalyzed C–h bond functionalization enabled by programmed alternating current

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Science China Chemistry 2025年第1期 10-11页

作者： Zhoumei Tan Kun xu Chengchu zeng Beijing Key Laboratory of Environmental and Viral Oncology College of Chemistry and Life Science Beijing University of Technology

Synthetic electrochemistry has been selected as one of the Top Ten Emerging Technologies in Chemistry in 2023 by International Union of Pure and Applied Chemistry (IUPAC)[1]. It has emerged as a sustainable platform for organic synthesis and has exhibited a wide range of applications from academia to industry [2]. however, electrosynthesis has been predominantly performed by using direct current (DC).

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Boosting hydrocarbon conversion via Cu-doping induced oxygen vacancies on CeO2 in CO2 electroreduction

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Journal of Energy Chemistry 2025年第1期100卷 66-76页

作者： Lei xue Tong Shi Chenhui han heng Zhang Fenrong Liu haorun Li Yan Wang xiaojun Gu Shanghong zeng Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials School of Chemistry and Chemical Engineering Inner Mongolia University State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Institute of Catalysis Department of Chemistry Zhejiang University National Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization Baotou Research Institute of Rare Earths

Conversion of CO2back to hydrocarbons is the most direct way of closing the“carbon cycle”,and its significance is further enlarged if this process is driven by renewable energies such as ***,precisely controlling the product selectivity towards hydrocarbons against the competitive hydrogen evolution remains challenging,especially for Cu-based ***,we report a novel defect engineering strategy,by which Cu-doping-induced oxygen vacancies on CeO2nanorods were effectively created,with adjustable vacancy/Cu *** resulting optimum catalyst shows up to 79% catalytic current density to hydrocarbons （excluding CO）,with 49% faradaic efficiency to *** and density functional theory unveil that the ratio between oxygen vacancy and Cu affects significantly the formation of*ChO and activation of h2O,which leads to the following deep hydrogenation to *** findings may spur new insights for designing and developing more controllable chemical process relevant to CO2utilization.

关键词： Nanorods

2D CaWO4 nanosheets derived from scheelite minerals for enhanced electrocatalysis in oxygen evolution reaction

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Science China Chemistry 2025年

作者： Qing Sun Yongxiang Sun Yan Dong hong Zhong hongbo zeng National&Local United Engineering Laboratory for New Petrochemical Materials&Fine Utilization of Resources College of Chemistry and Chemical EngineeringHunan Normal University Department of Chemical and Materials Engineering University of Alberta College of Chemistry and Materials Engineering Hunan University of Arts and Science College of Chemistry and Chemical Engineering Central South University

Scheelite （CaWO4） mineral holds promise as a cost-effective and efficient catalyst for the oxygen evolution reaction （OER）crucial in renewable energy ***,challenges such as limited active site exposure and low electrocatalytic performance need *** this work,we have fabricated two-dimensional （2D） CaWO4nanosheets from scheelite minerals via a straightforward ultrasonic exfoliation method and evaluated their efficacy as OER *** to scheelite powders,these 2D nanosheets exhibited superior crystallinity and a 1.26-fold increase in electrochemical surface area,promoting active site *** 2D CaWO4nanosheet electrode demonstrated outstanding OER catalytic performance,achieving a current density of 20 mA/cm2at an overpotential of 290 m V in alkaline conditions,which was lower than that of bulk CaWO4electrodes （～340 mV）.Density functional theory calculations attributed this enhanced catalytic performance to moderate adsorption of oxygenated intermediates （*Oh,*O,and*OOh） on the W sites of 2D *** situ electrochemical atomic force microscopy tests also confirmed the catalytic enhancement by 2D CaWO4nanosheets during *** findings demonstrate the potential of affordable and abundant mineral resources in advancing electrochemical catalysts for oxygen evolution,highlighting their broader application in sustainable energy technologies.

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Engineering high-performance chemiluminescent probes via enzymatic pocket targeting: high-throughput screening for ultralong afterglow imaging of orthotopic hepatocellular carcinoma

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Science China Chemistry 2025年

作者： Shuai huang Shuaige Bai Ting Luo Bin Feng Min Liu Fan Zheng Shuang huang Yanpeng Fang Dan Ding Wenbin zeng xiangya School of Pharmaceutical Sciences Central South University College of Life Sciences Nankai University

hepatocellular carcinoma （hCC） is a highly aggressive liver malignancy and the main form of liver cancer. Early diagnosis and treatment of hCC can effectively reduce mortality. Carboxylesterase （CE）-specific detection and imaging can be used for early diagnosis and image-guided surgical of hCC. however, traditional optical probes suffer from poor selectivity and low imaging signal-to-noise ratio. here, we have constructed a series of chemiluminescent probes for carboxylesterase detection based on the strategy of enzymatic pocket-oriented steric tailoring techniques. The probes with different unique and excellent properties have been obtained through the structure-based steric hindrance adjustment on the recognition site. here, CE-2 has been successfully used for high-throughput screening of rapid carboxylesterase inhibitors due to its extremely low detection limit (2.5×10-4U mL-1) and fast recognition ability. CE-3 has been successfully used for image-guided surgery of orthotopic hepatocellular carcinoma due to its ultra-long chemiluminescence imaging （over 12 h） of hepatocellular carcinoma. This study may promote advances in the rapid detection and screening of inhibitory drugs for CE and the field of surgical navigation in hCC.

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Improving the hard magnetic properties by intragrain pinning for Ta doped nanocrystalline Ce-Fe-B alloys

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Journal of Materials Science & Technology 2019年第9期35卷 1877-1885页

作者： J.S.Zhang W. Li x.F. Liao h.Y. Yu L.Z. Zhao h.x. zeng D.R. Peng Z.W. Liu School of Materials Science and Engineering South China University of TechnologyGuangzhou510640China Innovative Center for Advanced Materials (ICAM) Hangzhou Dianzi UniversityHangzhou310012China

To develop Ce based permanent magnets with high performance/cost ratio, Ta doping is was employed to enhance the magnetic performance of Ce-Fe-B alloys. For melt spun Cei7Fe78-xTaxB6 (x = 0-1) alloys, the coercivity hc increases from 439 to 553 kA/m with increasing x value from 0 to 0.75. Microstructure characterizations indicate that Ta doping is helpful for grain refinement. A second phase of TaB2 is observed in Ce17Fe77.25Tao.75B6 alloy, which acts as the pinning center of the magnetic domains, resulting in the change of coercivity mechanism from nucleation type to nucleation +pinning type. The micromagnetic simulation confirms that non-magnetic particles within hard magnetic phase can increase the demagnetization field around them and it is crucial for preventing the further magnetization reverse by pinning effect. Take the advantage of Ta doping for enhancing the coercivity, Ce content of Ce-Fe-B alloy can be further cut down to increase the remanence Jr due to the reduced volume fraction of CeFe2 phase and increased Fe/Ce ratio. As a result, a good combination of magnetic properties with hc = 514 kA/m, Jr = 0.49 T, and the maximum energy product (Bh)max = 36 kJ/m^3 have been obtained in Ce15Fe79.25Tao.75B6 alloy. It is expected that the present work can serve as a useful reference for designing new permanent magnetic materials with low-cost.

关键词： Melt-spinning Permanent magnets Second phase Coercivity mechanism Thermal stability

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Influence of alloy element partitioning on strength of primary α phase in Ti-6Al-4V alloy

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Journal of Materials Science & Technology 2018年第5期34卷 782-787页

作者： L.R.zeng h.L.Chen x.Li L.M.Lei G.P.Zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China University of Chinese Academy of Sciences Beijing 100049 China School of Materials Science and Engineering University of Science and Technology of China Shenyang 110016 China AVIC Commercial Aircraft Engine Co.LTD Shanghai 200241 China

The partitioning effect of Al（α-phase stabilizer） and V elements（β-phase stabilizer） on strength of the primary α phases in the α/β Ti-6 Al-4 V alloy with the bimodal microstructure was *** was found that partitioning of Al and V elements took place in the Ti-6 Al-4 V alloy during the recrystallization process,leading to the variation of the content of Al and V elements in the primary α phases with changing the volume fraction of the primary α *** tests reveal a general trend that the strength of the primary α phases increases with decreasing the volume fraction of the primary α phases,and such trend is independent on the loading direction relative to the c-axis of the α *** enhanced strength is attributed to the increase of the content of Al element in the primary α phase,but it is not dominated evidently by the change of the V *** solid solution strengthening contributed from both the elastic strain introduced by the solute atoms and the variation of the density of states was estimated theoretically.

关键词： Ti-6Al-4V Nanoindentation Strength Alloy element partitioning Crystallographic orientation

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It takes a team: a gairvof-function story of p53-R249S

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Journal of Molecular Cell Biology 2019年第4期11卷 277-283页

作者： huai Wang Peng Liao Shelya x. zeng hua Lu Department of Biochemistry and Molecular Biology Tulane Cancer Center Tulane University School of Medicine New Orleans LA 70112 USA School of Public health Nanchang University Nanchang 330006 China Jiangxi Provincial Key Laboratory of Preventive Medicine Nanchang University Nanchang 330006 China

Gain-of-function (GOF), the most malicious oncogenic activity of a cancer-promoting protein, is well illustrated to three hotspot p53 mutations at R248, R175, and R273 with distinct molecular mechanisms. Yet, less is known about another hotspot p53 mutant, R249S (p53-R249S). p53-R249S is the sole hotspot mutation in hepatocellular carcinoma (hCC) that is highly associated with chronic hepatitis B virus (hBV) infection and dietary exposure to aflatoxin B1 (AFB1). Its GOF is suggested by the facts that this mutant is associated with earlier onset of hCC and poorer prognosis of cancer patients and that its overexpression drives hCC proliferation and tumorigenesis. By contrast, simply knocking in this mutant in normal mice did not show apparent GOF activity. hence, the GOF activity for p53-R249S and its underlying mechanisms have been elusive until recent findings offered some new insights. This review will discuss these findings as well as their clinical significance and implications for the development of a strategy to target multiple molecules as a therapy for p53-R249S-harboring hCC.

关键词： p53-R249S Liver cancer hCC CDK4/cyclin D1 PIN1 c-Myc FBW7a

Potassium ions and cyano group modified g-C3N4 for effective generation of h2O2 through two-electron oxygen reduction

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Science China Chemistry 2025年第1期 192-200页

作者： Dongying Wang Shulan Pu Yongmin Chen Ke Lei Yujie Duan Linjiao Mao xuhui zeng xi Luo Yuntao Zhang Yuqin Dong Jin Zhong Zhang Yan Sun School of Mechanical Engineering Chengdu University Department of Chemistry and Biochemistry University of California

Potassium ions （K+） doped graphitic carbon nitride （g-C3N4） was prepared by a thermal etching method using potassium hydroxide （KOh） as an ion *** transform infrared spectroscopy （FTIR） and x-ray photoelectron spectroscopy （xPS）results showed that the generation of the cyano group was detected while introducing K+.Under simulated sunlight irradiation,the sample with a K+doping amount of 10%showed the highest hydrogen peroxide （h2O2） generation rate of2,140.2μmol *** apparent quantum yield （AQY） at 400 nm and the solar-to-chemical conversion （SCC） are 4.35%and1.23%,respectively.K+acted as a bridge between g-C3N4layers,which enhanced charge transfer ***,the cyano group enhanced the adsorption capacity of protons （h+） and promoted the yield of *** catalyst exhibited excellent photocatalytic stability based on four-cycle *** addition,a mechanism study showed that superoxide radicals （·O2-）were the most important active species in the reaction *** production of h2O2was achieved through consecutive single-electron *** study deepens the understanding of the oxygen reduction reaction process and opens up a new venue for improving h2O2generation.

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