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Science China Chemistry 2024年第5期67卷 1384-1396页

作者： Mengfu dai Liangliang Song Liang-An Chen Jiangsu Collaborative Innovation Center of Biomedical Functional Materials Jiangsu Key Laboratory of New Power BatteriesSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Chemical EngineeringNanjing Forestry UniversityNanjing 210037China

1,3-Diene architectures are not only widely present in natural products, pharmaceuticals, and functional organic materials but also serve as versatile building blocks to furnish important functionalized molecules in synthetic chemistry due to conjugated repeating C=C units. Accordingly, various strategies to access substituted 1,3-dienes in a stereoselective manner have been developed. However, chemo-, regio-and stereoselective synthesis of highly substituted 1,3-dienes still remains elusive and challenging. Readily available propargylic esters have emerged as an appealing class of synthetic intermediates for accessing functionalized 1,3-dienes, especially challenging tri-or tetrasubstituted variants, via transition-metal catalysis, including electrophilic metal and redox neutral catalysis. This review, for the first time, systematically highlights recent advances in transitionmetal catalyzed synthesis of substituted 1,3-dienes from propargylic esters, discusses the mechanisms and synthetic utilities, and gives the remaining challenges and potential opportunities in this field.

关键词： 1 3-diene propargylic ester Lewis acid redox catalysis transition metal

Robust Feedback Set Stabilization of Logic Networks with State-Dependent Uncertain Switching and Control Constraints

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Journal of Systems Science & Complexity 2024年第2期37卷 629-646页

作者： dai Chaoqun GUO Yuqian GUI Weihua School of Automation Central South UniversityChangsha 410083China

This study investigates the robust feedback set stabilization of switched logic control networks(SLCNs)with state-dependent uncertain switching and control ***,based on the properties of the semi-tensor product of matrices and the vector representation of logic,an SLCN with state-dependent uncertain switching and control constraints is expressed in algebraic ***,an input transformation and a switching model are constructed to transfer the original SLCN into one with a free control input and arbitrary *** equivalence between the set stabilizability of the original SLCN and that of the resulting SLCN is *** on such equivalence,the authors propose a necessary and sufficient condition for robust feedback set ***,an example is presented to demonstrate the application of the results obtained.

关键词： Input transformation robust control invariant subset robust feedback set stabilizability semi-tensor product state-dependent constraints switched logic control network

Tuning interaction strength between CeO_(2) and iridium to promote CO oxidation over Ir/TiO_(2)

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Journal of Rare Earths 2024年第4期42卷 651-659页

作者： Lu dai Binghua Li Yuhan peng Xianwei Hao Runquan Xuan Hua Huang Yiming Bi Liping Xu Yanhui Zhang Yun Guo Fangqi Du Li Wang Hui Wang Technology Center China Tobacco Zhejiang Industrial Co.Ltd.Hangzhou310024China Research Institute of Industrial Catalysis East China University of Science and TechnologyShanghai200237China

The interaction between support and noble metal plays a crucial role in heterogeneous catalysis ***,how to tune metal support interactions to optimize the activity still needs further ***_(2) was introduced to promote CO oxidation ove r Ir/TiO_(2) by adjusting the interaction strength between iridium(Ir)and CeO_(2).The strong interaction between Ir and CeO_(2) blocks CO adsorption and causes low CO oxidation ***,introducing CeO_(2) on Ir/TiO_(2) produces localized interaction between Ir and CeO_(2),which can tune the surface electronic state of Ir,so a"volcano curve"relationship between CO oxidation activity and electronic state is *** amount of CeO_(2) on Ir/TiO_(2)(Ir/Ce_(0.2)Ti)leads to CO complete oxidization at 22℃,and a new pathway for CO oxidation was *** study demonstrates that the utilization of tuning interaction strength between active metal and support is a potential method to increase the catalytic activity.

关键词： CO oxidation CeO_(2) Localized interaction Interaction strength Supported Ir catalysts Rareearths

Optimizing anaerobic digestion: Benefits of mild temperature transition from thermophilic to mesophilic conditions

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Environmental Science and Ecotechnology 2024年第5期21卷 381-395页

作者： Xingxing Zhang pengbo Jiao Yiwei Wang Yinying dai Ming Zhang peng Wu Liping Ma Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration Shanghai Engineering Research Center of Biotransformation of Organic Solid WasteSchool of Ecological and Environmental SciencesEast China Normal UniversityShanghai200241China School of Environmental Science and Engineering Suzhou University of Science and TechnologySuzhou215009China Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area Ministry of Natural ResourcesShanghai200062China

Anaerobic digestion(AD)plays a significant role in renewable energy *** AD from thermophilic(50e57C)to mesophilic(30e38C)conditions to enhance process stability and reduce energy input remains challenging due to the high sensitivity of thermophilic microbiomes to temperature *** we compare the effects of two decreasing-temperature modes from 55 to 35C on cell viability,microbial dynamics,and interspecies interactions.A sharp transition(ST)is a one-step transition by 20C d1,while a mild transition(MT)is a stepwise transition by 1C *** find a greater decrease in methane production with ST(88.8%)compared to MT(38.9%)during the transition *** mode overproduced reactive oxygen species by 1.6-fold,increased membrane permeability by 2.2-fold,and downregulated microbial energy metabolism by 25.1%,leading to increased apoptosis of anaerobes by 1.9-fold and release of intracellular substances by 2.9-fold,further constraining *** higher(1.6 vs.1.1 copies per gyrA)metabolic activity of acetate-dependent methanogenesis implied more efficient methane production in a steady mesophilic,MT-mediated *** binning and network analyses indicated that ST induced dysbiosis in keystone species and greatly enhanced microbial functional redundancy,causing loss of microbial syntrophic interactions and redundant metabolic *** contrast,the greater microbial interconnections(average degrees 44.9 vs.22.1)in MT at a steady mesophilic state suggested that MT could better maintain necessary system functionality and stability through microbial syntrophy or specialized *** MT to transform thermophilic digesters into mesophilic digesters is feasible and could potentially enhance the further optimization and broader application of practical anaerobic engineering.

关键词： Temperature transition Methane production Cellular viability Microbial community Metagenomic binning

Research on Alliance Decision of Dual-Channel Remanufacturing Supply Chain Considering Bidirectional Free-Riding and Cost-Sharing

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2913-2956页

作者： Lina Dong Yeming dai School of Business Qingdao UniversityQingdaoChina

This study delves into the formation dynamics of alliances within a closed-loop supply chain(CLSC)that encom-passes a manufacturer,a retailer,and an e-commerce *** leverages Stackelberg game for this exploration,contrasting the equilibrium outcomes of a non-alliance model with those of three differentiated alliance *** non-alliance model acts as a crucial benchmark,enabling the evaluation of the motivations for various supply chain entities to engage in alliance *** analysis is centered on identifying the most effective alliance strategies and establishing a coordination within these *** thoroughly investigate the consequences of diverse alliance behaviors,bidirectional free-riding and cost-sharing,and the resultant effects on the optimal decision-making among supply chain *** findings underscore several pivotal insights:(1)The behavior of alliances within the supply chain exerts variable impacts on the optimal pricing and demand of its *** comparison to the non-alliance(D)model,the manufacturer-retailer(MR)and manufacturer-e-commerce platform(ME)alliances significantly lower both offline and online resale prices for new and remanufactured *** adjustment leads to an enhanced demand for products via the MR alliance’s offline outlets and the ME alliance’s online platforms,thereby augmenting the profits for those within the ***,retailer-e-commerce platform(ER)alliance tends to increase the optimal retail price and demand across both online and offline *** specific conditions,alliance behavior can also increase the profits of non-alliance members,and the profits derived through alliance channels also exceed those from non-alliance channels.(2)The prevalence of bidirectional free-riding behavior largely remains constant across different alliance *** these models,bidirectional free-riding typically elevates the equilibrium prices in offline channel while negatively affe

关键词： Dual-channel remanufacturing supply chain alliance remanufactured products bidirectional free-riding cost-sharing

Jackson-type inequalities on high-dimensional spheres

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Science China Mathematics 2024年第11期67卷 2571-2586页

作者： Yeli Niu Feng dai Department of Mathematics Shanghai Normal University Department of Mathematical and Statistical Sciences University of Alberta

We study Jackson's inequality on high-dimensional spheres with respect to the modulus of smoothness defined via the rotation *** obtain a version of Jackson's inequality with a dimensionfree constant,extending Newman and Shapiro's well-known results in 1964 from the case of r = 1 and p = ∞ to more general *** results partially overcome the curse of *** also establish similar results on the equivalence of the K-functional and modulus of smoothness.

关键词： modulus of smoothness $K$-functional Jackson's inequality high-dimensional approximation

Pursue the nature of science: Advocate for a better research environment

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The Innovation 2024年第5期5卷 3-4页

作者： Ji dai Shenzhen Technological Research Center for Primate Translational Medicine Shenzhen-Hong Kong Institute of Brain ScienceShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China CAS Key Laboratory of Brain Connectome and Manipulation the Brain Cognition and Brain Disease InstituteShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Guangdong Provincial Key Laboratory of Brain Connectome and Behavior Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China University of Chinese Academy of Sciences Beijing 100049China

WHAT IS REAL SCIENCE?Science is often viewed through the lens of its tangible outcomes—publications,grants,academic titles,and *** markers of success in the academic world are undoubtedly important and serve as measures of productivity and ***,focusing solely on these external rewards risks oversimplifying the true essence of science and overlooking its fundamental purpose—the pursuit of knowledge through a process of discovery.1 At its core,science is a systematic and methodical approach to understanding the natural world,unraveling its mysteries,and uncovering the underlying principles that govern the *** is a process of inquiry and exploration that is driven by curiosity,creativity,and a relentless quest for truth(Figure 1).Science is not merely a means to an end but a journey of discovery that transcends individual accomplishments and external *** example is the study of gravitational waves,which are ripples in the fabric of spacetime and are predicted by Einstein’s theory of general *** 2015,the Laser Interferometer Gravitational-Wave Observatory(LIGO)detected gravitational waves for the first *** a major scientific breakthrough was the result of a collaboration between physicists and engineers from multiple institutions around the world,and it was also the result of pure curiosity.

关键词： doubt breakthrough Figure

Even-odd layer-dependent multiferroic in freestanding rare-earth orthorhombic perovskite

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 151-157页

作者： Shaowen Xu Fanhao Jia Ning dai School of Physics and Optoelectronic Engineering Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China Department of Physics College of ScienceHangzhou Dianzi UniversityHangzhou 310018China State Key Laboratory of Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083China

Freestanding oxide perovskites possess strong interlayer coupling between adjacent atomic layers,thus exerting a determinative effect on the magnetism and ferroelectricity of these atomic-scale ***,we propose an effective strategy to manipulate magnetism and ferroelectricity in freestanding rare-earth orthorhombic perovskite via modulation of layer *** performing first-principles calculations,an even-odd oscillation is demonstrated in few-layer GdAlO_(3)perovskite(GAP).Specifically,odd-layer systems with charged atomic layers are ferromagnetic polar metals,while even-layer systems are antiferromagnetic ferroelectric *** thickness-dependent magnetic phase transition originates from carrier doping,as rationalized by the Stoner ***,we demonstrate the promotion of in-plane ferroelectricity via the concurrent application of two distinct antiferrodistortive displacements,each driven by formation and breaking of *** multiferroic phases may emerge in other transition metal oxide perovskites supporting multiple valence states,e.g.,few-layer Gd MO_(3)(M=V,Cr,Mn,and Ni).This work puts forward a strategy for layer thickness engineering of magnetism and ferroelectricity in 2D oxide perovskite multiferroic materials.

关键词： few-layer rare-earth perovskite multiferroicity size effect first principles calculations

Syntheses and properties of associative acrylamide copolymers containing short hydrophobic chains used in a friction reducer for slick-water fracturing

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Petroleum Science 2024年第3期21卷 1889-1901页

作者： Ya-Xing dai Xian-Li Zhang Si-Yuan Liu Feng-Run-Ze Zhang Yi-Xi Zhang Yu-Tong Sang Jing-Xi Zheng Zhao-Sheng Liu peng Zhang College of Chemistry and Chemical Engineering Chongqing University of Science and TechnologyChongqing401331China College of Ecology and Environment Chongqing Resources and Environmental Protection of UniversityChongqing401331China China China Property Project Department of Dezhou Mining Property Service CenterShengli Oilfield Company of SinopecDezhou253000ShandongChina

Two allyldimethylalkyl quaternary ammonium salt(AQAS)monomers,N,N-dimethylallylphenylpropylammonium bromide(AQAS1)and N,N-dimethylallylnonylammonium bromide(AQAS2),were synthesized and used to prepare modified polyacrylamide *** new drag reducers were synthesized from acrylamide(AM),sodium acrylate(Na AA)and a cationic modified monomer(AQAS1 or AQAS2)via aqueous solution polymerization,and the copolymers were named P(AM/Na AA/AQAS1)and P(AM/Na AA/AQAS2),*** structures of the drag reduction agents were confirmed by IR and1H NMR *** molecular weight(Mw)of P(AM/Na AA/AQAS1)was 1.79×10^(6)g/*** the copolymer concentration was 1000 mg/L and the flow rate was 45 L/min,in fresh water the highest drag reduction rate was 75.8%,in 10,000 mg/L Na Cl solution the drag reduction rate decreased to 72.9%.The molecular weight of P(AM/Na AA/AQAS2)was 3.17×10^(6)g/*** the copolymer concentration was500 mg/L and the flow rate was 45 L/min,the drag reduction rate reached 75.2%,and in 10,000 mg/L Na Cl solution the drag reduction rate was 73.3%,decreased by approximately 1.9%.The drag reduction rate for partially hydrolyzed polyacrylamide(HPAM)was also investigated,and the results showed that the drag reduction rates for 500 and 1000 mg/L HPAM solutions were merely 43.2%and 49.0%in brine,*** with HPAM,both of the above copolymers presented better drag reduction capacities.

关键词： Shale gas Slick water Drag reducer Modified monomer Copolymerization

Huaiyu pill(槐榆片) alleviates inflammatory bowel disease in mice via blocking toll like receptor 4/myeloid differentiation primary response gene 88/nuclear factor kappa B subunit 1 pathway

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Journal of Traditional Chinese Medicine 2024年第5期44卷 916-925页

作者： YANG Chunyan LUO Jia peng Weijie dai Weibo Department of Pharmacy Zhongshan Hospital of Traditional Chinese MedicineGuangzhou University of Traditional Chinese Medicine Department of Pharmacy Shenshan Medical Center Memorial Hospital of Sun Yat-Sen University Sun Yat-Sen University

OBJECTIVE: To investigate the therapeutic effects of Huaiyu pill(槐榆片, HYP) on inflammatory bowel disease(IBD) and the underlying mechanisms have not been elucidated. METHODS: To establish the IBD model, mice were administered with dextran sulfate sodium(DSS). Mice were intragastrically pre-treated with sulfasalazine(SASP) and HYP. Disease activity index(dai) and colon length were monitored, and the colonic tissues were subjected to hematoxylin-eosin staining. Pro-inflammatory factors and vascular inflammation-related proteins were determined using enzyme-linked immunosorbent assay(ELISA). The potential mechanisms of HYP were examined using network pharmacology *** expressions of zona occludens 1(ZO-1), occludin, toll like receptor 4(TLR4), myeloid differentiation primary response gene 88(MYD88), and nuclear factor kappa B p65 subunit(NF-κB p65) in colon tissues were examined using Western blotting or immunohistochemical analyses. RESULTS: Pre-treatment with HYP enhanced the colon length, decreased dai scores, and mitigated histopathological alterations in DSS-treated mice. HYP alleviated intestinal inflammation by downregulating the levels of interleukin 1 beta(IL-1β), interleukin 6(IL-6), tumor necrosis factor alpha(TNF-α) and interleukin 17(IL-17). Additionally, HYP suppressed the disruption of the gut barrier by upregulating the ZO-1, occludin, and mucin 2(MUC2) levels and downregulating the endothelin 1(ET-1) and erythropoietin(EPO) levels. Network pharmacological analysis and experimental results revealed that HYP downregulated the colonic tissue levels of TLR4, MYD88, and NF-κB p65 in DSStreated mice. CONCLUSION: This study investigated the in vivo therapeutic effects of HYP on IBD and the underlying molecular mechanisms. These findings provide an experimental foundation for the clinical application of HYP.

关键词： Huaiyu pill inflammatory bowel diseases intestinal damage intestinal inflammation network pharmacology