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Chinese Journal of Chemistry 2024年第10期42卷 1093-1099页

作者： Ying-Xia Wang Fang Zheng Dong-Xia Song bao-yue niu Lu-Qian Deng Xian-Ming Zhang Key Laboratory of Magnetic Molecules and Magnetic Information Materials(Ministry of Education) Schoolof Chemistry and Materials ScienceShanxi Normal UniversityTaiyuanShanxi 030006China Key Laboratory of Interface Science and Engineering in Advanced Material(Ministry of Education) College of ChemistryTaiyuan University of TechnologyTaiyuanShanxi 030024China

The photocatalytic oxidative coupling of thiols is one of the most popular methods to synthesize the *** and its derivatives(TPAs)are promising for the above reaction,but suffer from the easy polymerization and difficult *** overcome these obstacles while controlling the photogenerated electrons transfer directly to target substrates,herein,we constructed one TPA-based metal-organic framework(MOF),(Me_(2)NH_(2))[Sr(TCBPA)]·DMA·3H_(2)O(1),by direct self-assembly of tris(4′-carboxybiphenyl)amine(H_(3)TCBPA)and photoredox inert strontium ion(Sr^(2+)).DFT calculations revealed that the valence band maximum(VBM)and the conduction band minimum(CBM)are mainly located on TCBPA^(3-),successfully inhibiting the undesirable electron migration to metal *** results indicated that 1 displays superior performance than homogeneous H_(3)TCBPA,which may result from the abundant π…π and C—H…π interactions between the well-arranged TCBPA^(3-)and the build-in electric field between the anionic framework and the Me_(2)NH^(2+).This work highlights that immobilizing TPAs into MOFs is one promising approach to designing heterogeneous photocatalysts for the synthesis of disulfides by oxidative coupling of thiols.

关键词： Triphenylamine Metal-organic frameworks Strontium Photooxidation Thiols Disulfides

Applications of in-situ solid-state nuclear magnetic resonance in methanol to olefins reaction

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Science China Chemistry 2025年第1期68卷 134-151页

作者： Jing niu Shutao Xu Yingxu Wei Zhongmin Liu National Engineering Research Center of Lower-Carbon Catalysis Technology Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China

The methanol-to-olefins(MTO)reaction offers an alternative pathway for the production of low-carbon olefins from non-oil *** research has been impeded by a lack of comprehensive understanding of its underlying mechanism,despite the significant progress made in ***-situ solid-state nuclear magnetic resonance(ss NMR)spectroscopy has emerged as a pivotal tool,offering crucial insights into key species under real-time operando ***,the host–guest interaction between zeolites or surface species residing on zeolites and the reactant/active intermediates is revealed by the combination of in-situ^(13)C MAS NMR and 2D correlation ***,recent technological advancements in hyperpolarization(HP)methods,including HP^(129)Xe NMR and dynamic nuclear polarization(DNP),have significantly improved the sensitivity of ssNMR,enabling detailed structural and kinetic analysis as well as the detection of trace *** this feature article,we summarized recent advancements in(in-situ)ssNMR spectroscopy applied to MTO reaction processes,encompassing mechanistic investigations at various stages and the intricate host–guest *** theoretical insights into the dynamic evolution of MTO reactions lay a solid foundation for the optimization of catalytic processes and the development of efficient catalysts,thereby advancing the techniques towards more sustainable and economical production route for olefins.

关键词： MTO zeolites in-situ ssNMR reactive intermediates reaction mechanism

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Eigenvalue-Free Interval for Seidel Matrices of Cographs

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Journal of Mathematical Research with Applications 2025年第1期45卷 1-10页

作者： Heming niu Wei WANG School of Mathematics Physics and Finance Anhui Polytechnic University

Abstract The distribution of Seidel eigenvalues of cographs is investigated in this *** prove that there is no Seidel eigenvalue of nontrivial cographs in the interval (-1,1).We also show the optimality of the interval (-1,1) in the sense that for any■>0 either of the intervals(1,1+■) and (-1-■,-1) contains a Seidel eigenvalue of some cograph of order n when n is sufficiently large.

关键词： cograph Seidel matrix eigenvalue-free interval

Coating colloidal particles with a well-defined polymer layer by surface-initiated photoinduced polymerization-induced self-assembly and the subsequent seeded polymerization

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Chinese Chemical Letters 2025年第2期36卷 213-217页

作者： Bing niu Honggao Huang Liwei Luo Li Zhang Jianbo Tan Department of Polymeric Materials and Engineering School of Materials and EnergyGuangdong University of Technology Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter

Core-shell colloidal particles with a polymer layer have broad applications in different ***,we developed a two-step method combining aqueous surface-initiated photoinduced polymerization-induced self-assembly and photoinduced seeded reversible addition-fragmentation chain transfer (RAFT) polymerization to prepare a diverse set of core-shell colloidal particles with a well-defined polymer *** compositions,structures,and thicknesses of polymer layers could be conveniently regulated by using different types of monomers and feed[monomer]/[chain transfer agent]ratios during seeded RAFT polymerization.

关键词： Core-shell colloidal particles Photoinduced polymerization-induced self-assembly RAFT polymerization Seeded polymerization Surface-initiated polymerization

General Automatic Solution Generation for Social Problems

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Machine Intelligence Research 2025年第1期22卷 145-159页

作者： Tong niu Haoyu Huang Yu Du Weihao Zhang Luping Shi Rong Zhao Center for Brain-Inspired Computing Research(CBICR) Optical Memory National Engineering Research Centerand Department of Precision InstrumentTsinghua UniversityBeijing100084China IDG/McGovern Institute for Brain Research Tsinghua UniversityBeijing100084China THU-CET HIK Joint Research Center for Brain-Inspired Computing Beijing100084China

Given the escalating intricacy and multifaceted nature of contemporary social systems,manually generating solutions to address pertinent social issues has become a formidable *** response to this challenge,the rapid development of artificial intelligence has spurred the exploration of computational methodologies aimed at automatically generating ***,current methods for the auto-generation of solutions mainly concentrate on local social regulations that pertain to specific ***,we report an automatic social operating system(ASOS)designed for general social solution generation built upon agent-based models that enables both global and local analyses and regulations of social problems across spatial and temporal *** adopts a hypergraph with extensible social semantics for a comprehensive and structured representation of social *** also incorporates a generalized protocol for standardized hypergraph operations and a symbolic hybrid framework that delivers interpretable solutions,yielding a balance between regulatory efficacy and functional *** demonstrate the effectiveness of the ASOS,we apply it to the domain of averting extreme events within international oil futures *** generating a new trading role supplemented by new mechanisms,ASOS can adeptly discern precarious market conditions and make front-running interventions for nonprofit *** study demonstrated that ASOS provides an efficient and systematic approach for generating solutions for enhancing our society.

关键词： General automatic generation global-local regulation hypergraph social representation symbolic hybrid scheme generalized operation protocol

Two New Nonconforming Quadrilateral Finite Element Methods for the Brinkman Problem

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Journal of Mathematical Research with Applications 2025年第02期 243-259页

作者： Hexin niu Xinchen ZHOU School of Mathematical Sciences Jiangsu University

In this paper, two new efficient fully nonconforming polynomial finite element methods on arbitrary convex quadrilaterals are constructed to solve the Brinkman problem. Both elements have 12 local degrees of freedom and are uniformly first-order convergent. For the first element, we carefully design a shape function space of only degree four, which is convenient for practical computation. Meanwhile, the velocity solution obtained by our second element has O（h2） convergence order in the case of Darcy limit. These new elements can be regarded as modifications of a known element to effectively improve the computational efficiency, only the shape function space is properly changed. We verify our theoretical findings by numerical examples.

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Ubiquitin-specific protease 1 facilitates tumor immune escape from natural killer cells and predicts the prognosis in small cell lung cancer

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Oncology Research 2025年第1期33卷 213-224页

作者： SHIQIN JIANG YICHUN TANG FENG MA YUCHUN niu LEI SUN Department of Clinical Pharmacy Shenzhen Hospital of Integrated Traditional Chinese and Western MedicineShenzhen518104China Department of Pathology Zhujiang HospitalSouthern Medical UniversityGuangzhou510280China Department of Radiation Oncology The First People’s Hospital of FoshanFoshan528000China Department of Oncology The First Affiliated Hospital of Jinan UniversityJinan UniversityGuangzhou510630China Department of Oncology The First Dongguan Affiliated HospitalGuangdong Medical UniversityDongguan523721China

Objective:Small cell lung cancer(SCLC)is commonly recognized as the most fatal lung cancer *** substantial advances in immune checkpoint blockade therapies for treating solid cancers,their benefits are limited to a minority of patients with *** the present study,novel indicators for predicting the outcomes and molecular targets for SCLC treatment were ***:We conducted bioinformatics analysis to identify the key genes associated with tumor-infiltrating lymphocytes in *** functional role of the key gene identified in SCLC was determined both in vitro and in ***:A significant correlation was observed between patient survival and CD56dim natural killer(NK)cell ***,we noted that the hub gene ubiquitin-specific protease 1(USP1)is closely correlated with both CD56dim NK cells and overall survival in *** analysis revealed that USP1 is upregulated in *** addition,gene set enrichment analysis revealed that USP1 overexpression hinders NK cell-mediated immune *** co-cultivating NK-92 cells with SCLC cells,we demonstrated that NK cell cytotoxicity against SCLC could be improved either via USP1 knock-down or pharmacological ***,using a nude-mice xenograft tumor model,we noted that USP1 inhibition effectively suppressed tumor proliferation and increased the expression of NK cell-associated ***:Our study findings highlight the importance of NK cells in regulating ***1 overexpression can inhibit NK cell-mediated immunity;therefore,USP1 may serve not only as a prognostic biomarker but also as a potential molecular target of SCLC therapy.

关键词： Ubiquitin-specific protease 1(USP1) Natural killer(NK)cell Small cell lung cancer(SCLC) Prognosis Immune escape

Towards few-shot mixed-type dialogue generation

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Science China(Information Sciences) 2025年第2期68卷 120-133页

作者： Zeming LIU Haifeng WANG Zeyang LEI Zheng-Yu niu Hua WU Wanxiang CHE Research Center for Social Computing and Information Retrieval Baidu Inc.

Building an agent capable of conducting both open-domain and task-oriented dialogues, known as mixed-type dialogues, has been an enduring challenge for the AI community. Previous approaches have focused on constructing largescale human-annotated datasets for training models. However, annotating these datasets is expensive and hinders the practical application of these models. This paper identifies a novel challenge, few-shot mixed-type dialogue generation. To address this challenge, we first present a pre-trained dialogue generation framework with modular-based architecture and prompttuning component. Additionally, we collect a mixed-type dialogue dataset that combines persona-chat with conversational recommendation or task-oriented dialogues within a single dialogue session. Specifically, the modular-based architecture allows us to easily incorporate more supervised signals and human-annotated information, thereby facilitating the learning of sessionlevel dialogue logic. We pre-train this dialogue generation framework using multiple external datasets and then fine-tune it on the mixed-type dialogue dataset we collected. Experimental results demonstrate that the three key designs — modular-based architecture, prompt-tuning component, and model pre-training — significantly enhance the performance of this framework compared to state-of-the-art baselines.

关键词： mixed-type dialogue dialogue generation PLATO-prompt Mixed-FS few-shot

Novel Low-Carbon Optimal Operation Method for Flexible Distribution Network Based on Carbon Emission Flow

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Energy Engineering 2025年第2期122卷 785-803页

作者： Chao Gao Kai niu Wenjing Chen Changwei Wang Yabin Chen Rui Qu Guangdong-Hong Kong-Macao Greater Bay Area Construction Promotion Office of Guangdong Power Grid Co. Ltd.Guangzhou510030China School of Electrical Engineering Northeast Electric Power UniversityJilin132012China School of Electrical Engineering Fuzhou UniversityFuzhou350116China

With the widespread implementation of distributed generation(DG)and the integration of soft open point(SOP)into the distribution network(DN),the latter is steadily transitioning into a flexible distribution network(FDN),the calculation of carbon flow distribution in FDN is more *** this end,this study constructs a model for low-carbon optimal operations within the FDN on the basis of enhanced carbon emission flow(CEF).First,the carbon emission characteristics of FDNs are scrutinized and an improved method for calculating carbon flow within these networks is ***,a model for optimizing low-carbon operations within FDNs is formulated based on the refined CEF,which merges the specificities of DG and intelligent ***,this model is scrutinized using an upgraded IEEE 33-node distribution system,a comparative analysis of the cases reveals that when DG and SOP are operated in a coordinated manner in the FDN,with the cost of electricity generation was reduced by 40.63 percent and the cost of carbon emissions by 10.18 *** findings indicate that the judicious optimization of areas exhibiting higher carbon flow rates can effectively enhance the economic efficiency of DN operations and curtail the carbon emissions of the overall network.

关键词： Flexible distribution network carbon emission flow distributed generation soft open points

Weak KAM theory for two classes of almost periodic Hamiltonian systems

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Science China Mathematics 2025年

作者： Xun niu Kaizhi Wang Yong Li School of Mathematics and Statistics Center for Mathematics and Interdisciplinary SciencesNortheast Normal University School of Mathematical Sciences Shanghai Frontier Science Center of Modern Analysis (CMA-Shanghai)Shanghai Jiao Tong University Institute of Mathematics Jilin University

The purpose of this paper is to investigate the dynamics of Bohr almost periodic and Levitan almost periodic Hamiltonian systems via the weak KAM theory. We obtain minimal measures and weak KAM solutions in both cases. The weak KAM solution is a weak solution to the Hamilton-Jacobi equation, which formally transforms the original Hamiltonian systems into an integrable one. Consequently, we get the existence of an invariant torus in the aforementioned weak sense.

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