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Negative enthalpy alloys and local chemical ordering:a concept and route leading to synergy of strength and ductility

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National science Review 2024年第4期11卷 172-184页

作者： Zibing An Tao Yang Caijuan Shi Shengcheng Mao Lihua Wang Ang Li Wei Li Xianmeng Xue Ming Sun Yifan Bai Yapeng He Fuzeng Ren Zhouguang Lu Ming Yan Yang Ren Chain-Tsuan Liu Ze Zhang Xiaodong Han Beijing Key Lab of Microstructure and Property of Advanced Materials College of Materials Science &Engineering Beijing University of Technology department of Materials science and Engineering City University of Hong Kong Key Laboratory of Partial Acceleration Physics& Technology Institute of High Energy PhysicsChinese Academy of Sciences department of Materials science &Engineering Southern University of Science and Technology department of Physics City University of Hong Kong State Key Laboratory of Silicon Materials Department of Materials Science and Engineering Zhejiang University

Solid solutions are ubiquitous in metals and alloys. Local chemical ordering(LCO) is a fundamental sub-nano/nanoscale process that occurs in many solid solutions and can be used as a microstructure to optimize strength and ductility. However, the formation of LCO has not been fully elucidated, let alone how to provide efficient routes for designing LCO to achieve synergistic effects on both superb strength and ductility. Herein, we propose the formation and control of LCO in negative enthalpy alloys. With engineering negative enthalpy in solid solutions, genetic LCO components are formed in negative enthalpy refractory high-entropy alloys(RHEAs). In contrast to conventional ‘trial-and-error' approaches, the control of LCO by using engineering negative enthalpy in RHEAs is instructive and results in superior strength(1160 MPa) and uniform ductility(24.5%) under tension at ambient temperature, which are among the best reported so far. LCO can promote dislocation cross-slip, enhancing the interaction between dislocations and their accumulation at large tensile strains; sustainable strain hardening can thereby be attained to ensure high ductility of the alloy. This work paves the way for new research fields on negative enthalpy solid solutions and alloys for the synergy of strength and ductility as well as new functions.

关键词： negative enthalpy alloys local chemical ordering strength ductility dislocation

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Rhodium-catalyzed addition reactions of benzylic C–H bonds to cyclic N-sulfonyl ketimines viaπ-coordination

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Chinese Chemical Letters 2024年第3期35卷 287-291页

作者： Yuntong Li Hang Shi department of Chemistry Zhejiang UniversityHangzhou 310027China Key Laboratory of Precise Synthesis of functional Molecules of Zhejiang Province Department of ChemistrySchool of Science and Research Center for Industries of the FutureWestlake UniversityHangzhou 310030China Institute of Natural sciences Westlake Institute for Advanced StudyHangzhou 310024China

Mannich-type reactions are a widely used method for the synthesis of amines due to the readily availability of nucleophiles and electrophiles.However,the inclusion of alkylarenes instead of active carbon pronucleophiles such as aldehydes and ketones in these addition reactions has been a challenge due to the inherent difficulty of benzylic deprotonation.In this study,we present a novel approach for the construction of N-sulfonyl amines via rhodium-catalyzed addition of unbiased benzylic C–H bonds to cyclic N-sulfonyl ketamines throughπ-coordination.This strategy enables the synthesis of a diverse range of N-sulfonyl amines,and subsequent diversification of the addition products showcases the synthetic potential of this protocol.

关键词： Benzylic deprotonation Cyclic N–sulfonyl ketimines π-Coordination Mannich-type addition Rhodium catalysis

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Categorizing methods for integrating machine learning with executable specifications

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science China(Information sciences) 2024年第1期67卷 5-19页

作者： David HAREL Raz YERUSHALMI Assaf MARRON Achiya ELYASAF department of Computer science and Applied Mathematics Weizmann Institute of Science department of Software and Information Systems Engineering Ben-Gurion University of the Negev

Deep learning(DL),which includes deep reinforcement learning(DRL),holds great promise for carrying out real-world tasks that human minds seem to cope with quite readily.That promise is already delivering extremely impressive results in a variety of areas.However,while DL-enabled systems achieve excellent performance,they are far from perfect.It has been demonstrated,in several domains,that DL systems can err when they encounter cases they had not hitherto encountered.Furthermore,the opacity of the produced agents makes it difficult to explain their behavior and ensure that they adhere to various requirements posed by human engineers.At the other end of the software development spectrum of methods,behavioral programming(BP) facilitates orderly system development using self-standing executable modules aligned with how humans intuitively describe desired system behavior.In this paper,we elaborate on different approaches for combining DRL with BP and,more generally,machine learning(ML) with executable specifications(ES).We begin by defining a framework for studying the various approaches,which can also be used to study new emerging approaches not covered here.We then briefly review state-of-the-art approaches to integrating ML with ES,continue with a focus on DRL,and then present the merits of integrating ML with BP.We conclude with guidelines on how this categorization can be used in decision making in system development,and outline future research challenges.

关键词： machine learning artificial intelligence grey box learning domain knowledge rules behavioral programming deep reinforcement learning survey

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Rosmarinic acid regulates lipid accumulation through lipid metabolism and anti-inflammatory

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Food science and Human Wellness 2024年

作者： Chunxiu Lin Zhuobin Li Yun Chen Jingrui Luo Guo Liu Chitang Ho Yong Cao Yunjiao Chen Guangdong Provincial Key Laboratory of Nutraceuticals and functional Foods College of Food science South China Agricultural University Guangdong Laboratory for Lingnan Modern Agriculture department of Food science Rutgers University New Brunswick

Obesity caused by poor eating habits has become a global public health issue and harms human health. Rosmarinic acid (RA) is a natural active substance with many biological functions like antioxidant. However， the function of RA’s lipid-lowering effect and mechanism are not entirely clear. This study aimed to explore the effect of RA on obesity and its action mechanism in Caenorhabditis elegans. RA not only alleviated intestinal inflammation and change the composition of unsaturated fatty acid， but also decreased fat storage and adjusted the size and quantity of fat droplets without threatening development and reproduction or affecting energy intake. In addition， RA improved the integrity of intestinal barrier function in C. elegans. RNA sequencing and qRT-PCR comprehensively revealed that the lipid-lowering mechanism mediated by RA might involve lipid metabolism and anti-inflammatory pathways. Among them， RA regulates lipid metabolism by reducing fat synthesis through SBP-1and increasing fatty acid β-oxidation via NHR-49. Furthermore， the anti-inflammatory pathway was associated with RA’s enhancement of the ratio of unsaturated fatty acid and alleviation of inflammatory reactions caused by PAO1. Therefore， RA regulated lipid metabolism and relieved inflammation， which had the potential for dietary supplements or functional foods.

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Combined Treatment with Bojungikgi-tang(Buzhong Yiqi Decoction) and Riluzole Attenuates Cell Death in TDP-43-Expressing Cells

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Chinese Journal of Integrative Medicine 2024年第7期30卷 616-622页

作者： Eun Jin Yang department of KM science Research Korea Institute of Oriental Medicine

Objective: To examine the effect of combined treatment with Bojungikgi-tang(BJIGT, Buzhong Yiqi Decoction) and riluzole(RZ) in transactive response DNA-binding protein 43(TDP-43) stress granule(SG) cells, a amyotrophic lateral sclerosis(ALS) cell line using transcriptomic and molecular techniques. Methods: TDP-43 SG cells were pretreated with BJIGT(100 μg/mL), RZ(50 μmol/L), and combined BJIGT(100 μg/mL)/RZ(50 μmol/L) for 6 h before treatment with lipopolysaccharide(LPS, 200 μmol/L). Cell viability assay was performed to elucidate cell toxicity in TDP-43 SC cells using a cell-counting kit-8(CCK8) assay kit. The expression levels of cell death-related proteins, including Bax, caspase 1, cleaved caspase 3 and DJ1 in TDP-43 SG cells were examined by Western blot analysis. The autophagy-related proteins, including pmTOR/mTOR, LC3b, P62, ATG7 and Bcl-2-associated athanogene 3(Bag3) were investigated using immunofluorescence and immunoblotting assays. Results: Cell viability assay and Western blot analysis showed that combined treatment with BJIGT and RZ suppressed LPS-induced cell death and expression of cell death-related proteins, including Bax, caspase 1, and DJ1(P<0.05 or P<0.01). Immunofluorescence and immunoblotting assays showed that combined treatment with BJIGT and RZ reduced LPS-induced formation of TDP-43 aggregates and regulated autophagy-related protein levels, including p62, light chain 3b, Bag3, and ATG7, in TDP-43-expressing cells(P<0.05 or P<0.01). Conclusion: The combined treatment of BJIGT and RZ might reduce inflammation and regulate autophagy dysfunction in TDP-43-induced ALS.

关键词： Bojungikgi-tang Buzhong Yiqi Decoction transactive response DNA-binding protein 43 autophagy oxidative stress amyotrophic lateral sclerosis

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Development of porphyrin-based fluorescent sensors and sensor arrays for saccharide recognition

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Chinese Chemical Letters 2024年第2期35卷 16-23页

作者： Yubin Ding Jiaxin Wang Ruinan Wang Yongshu Xie department of Chemistry College of SciencesNanjing Agricultural UniversityNanjing 210095China Shanghai Key Laboratory of functional Materials Chemistry Key Laboratory for Advanced Materials and Institute of Fine ChemicalsSchool of Chemistry and Molecular EngineeringEast China University of Science & TechnologyShanghai 200237China

Saccharide sensing is a very meaningful research topic as saccharides are involved in many biological activities.However,it is challenging to design molecular sensors for saccharides because this family of compounds is hydromimetic in aqueous solutions and shares a similar chemical structure.In this review,research progress in the development of porphyrin-based saccharide sensors is described with representative examples.We focus on using porphyrin as the signal reporter because porphyrins exhibit unique advantages in high chemical stability,long emission wavelength,and multiple structural modification strategies.Reported literature results have been classified into mainly two sections according to the general working principles of the porphyrin sensor molecules.In the first section,recognition unit,design strategy and sensing performance of traditional porphyrin-based selective saccharide sensors are discussed.While in the second section,development of porphyrin-based sensor arrays for pattern recognition of saccharides has been summarized.Looking through the design strategy and sensing performance of reported achievements,it is reasonable to anticipate a bright future for designing practical porphyrin-based saccharide sensors.

关键词： Porphyrin Saccharide Fluorescent sensing Selective sensing Pattern recognition

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Bright dual-color electrochemiluminescence of a structurally determined Pt1Ag18 nanocluster

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Aggregate 2024年第1期5卷 345-352页

作者： Bing Yin Lirong Jiang Xiaojian Wang Ying Liu Kaiyang Kuang Mengmeng Jing Chunmin Fang Chuanjun Zhou Shuang Chen Manzhou Zhu Institutes of Physical science and Information Technology and Centre for Atomic Engineering of Advanced Materials Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationDepartment of Chemistry and Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized MaterialsAnhui UniversityHefeiChina

Metal nanoclusters possess excellent electrochemical,optical,and catalytic properties,but correlating these properties remains challenging,which is the foundation to generate electrochemiluminescence(ECL).Herein,we report for the first time that a structurally determined Pt1Ag18 nanocluster generates intense ECL and simultaneously enhances the ECL of carbon dots(CDs)via an electrocatalytic effect.Pt^(1)Ag_(18)nanocluster show aggregation-induced emission enhancement and aggregation-induced ECL enhancement under light and electrochemical stimulation,respectively.In the presence of tripropylamine(TPrA)as a coreactant,solid Pt1Ag18 shows unprecedented ECL efficiency,which is more than nine times higher than that of 1 mM Ru(bpy)32+with the same TPrA concentration.Potential-resolved ECL spectra reveal two ECL emission bands in the presence of TPrA.The ECL emission centered at 650 nm is assigned to the solid Pt_(1)Ag_(18)nanocluster,consistent with the peak wavelength in self-annihilation ECL and photoluminescence of the solid state.The ECL emission centered at 820 nm is assigned to the CDs on the glassy carbon electrode.The electrocatalytic effect of the nanoclusters enhanced the ECL of the CDs by a factor of more than 180 in comparison to that without nanoclusters.Based on the combined optical and electrochemical results,the ECL generation pathways and mechanisms of Pt1Ag18 and CDs are proposed.These findings are extremely promising for designing multifunctional nanocluster luminophores with strong emissions and developing ratiometric sensing devices.

关键词： AIECLE AIEE electrochemiluminescence nanocluster photoluminescence structure

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What can we learn from quality assurance badges in open-source software?

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science China(Information sciences) 2024年第4期67卷 146-163页

作者： Feng LI Yiling LOU Xin TAN Zhenpeng CHEN Jinhao DONG Yang LI Xuanzhi WANG Dan HAO Lu ZHANG MoE Key Lab of HCST School of Computer SciencePeking University department of Computer science Purdue University School of Computer science & Engineering Beihang University(BUAA) department of Computer science University College London(UCL)

In the development of open-source software(OSS), many developers use badges to give an overview of the software and share some key features/metrics conveniently. Among various badges, quality assurance(QA) badges make up a large proportion and are the most prevalent because QA is of vital importance in software development, and ineffective QA may lead to anomalies or defects. In this paper, we focus on QA badges in open-source projects, which present quality assurance information directly and instantly,and aim to produce some interesting findings and provide practical implications. We collect and analyze 100000 projects written in popular programming languages from GitHub and conduct a comprehensive empirical study both inside and outside QA badges. Inside QA badges, we build a category classification for all QA badges based on the properties they focus on, which shows the types of QA badges developers use. Then,we analyze the frequency of the properties that QA badges focus on, and property combinations, too, which present their use status. We find that QA badges focus on various properties while developers give different preferences to different properties. The use status also differs between different programming languages. For example, projects written in C focus on Security to a great extent. Our findings also provide implications for developers and badge providers. Outside QA badges, we conduct a correlation analysis between QA badges and some software metrics that have potential relationships with code quality, contribution quality, and popularity. We find that QA badges have statistically significant correlations with various software metrics.

关键词： quality assurance badge open-source software code quality empirical study

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Semicrystalline Unfused Polymer Donors with Backbone Halogenation toward Cost-Effective Organic Solar Cells

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Chinese Journal of Chemistry 2024年第7期42卷 752-759页

作者： Yuxin Kong Shijie Ju Hongmei Qin Min Hun Jee Simeng Xia Jiaqi Ren Chao Gao Jianyu Yuan Wenyan Su Han Young Woo Yuxiang Li School of Materials science and Engineering Xi'an University of Science and TechnologyXianShaanxi 710054China department of Chemistry Korea UniversitySeoul 02841Republic of Korea Xi'an Key Laboratory of Liquid Crystal and Organic Photovoltaic Materials State Key Laboratory of Fluorine&Nitrogen ChemicalsXi'an Modern Chemistry Research InstituteXi'anShaanxi 710065China Jiangsu Key Laboratory for Carbon-Based functional Materials&Devices Institute of Functional Nano&Soft Materials(FUNSOM)Soochow University199 Ren'ai RoadSuzhouJiangsu 215123China

Developing novel unfused building blocks with simple synthesis and low cost is essential to advance and enrich cost-effective poly-mer donors;however,it remains a challenge due to the lack of efficient molecular strategies.Herein,a class of low-cost and fully unfused polymer donors with precisely regulated backbone planarity via halogenation was designed and synthesized,namely PDTBTBz-2H,PDTBTBz-2F,and PDTBTBz-2Cl.These polymer donors possess a four-step synthesis route with over 80%yield from cheap raw chemicals comparable to existing low-cost polymer donors,such as PTQ10.Benefitting from the planar backbone via in-corporating the F…S non-covalent interactions,PDTBTBz-2F exhibits more robust J-type aggregation in solution and a long-ranged molecular stacking in film relative to PDTBTBz-2H and PDTBTBz-2Cl.Moreover,the systematical study of PDTBTBz-based organic so-lar cells(OSCs)reveals the close relationship between optimized molecular self-assembly and charge separation/transport regarding backbone halogenation when paired with the non-fullerene acceptor(Y6-BO-4F).As a result,the photovoltaic devices based on semicrystalline PDTBTBz-2F achieved a promising power conversion efficiency(PCE)of 12.37%.Our work highlighted the influence of backbone halogenation on the molecular self-assembly properties and a potential unfused backbone motif for further developing cost-effective OSCs.

关键词： Low-cost Polymer donors Backbone halogenation Molecular self-assembly Organic solar cells

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Synthesis and characterization of iron clusters with an icosahedral [Fe@Fe12]16+ Core

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National science Review 2024年第4期11卷 123-129页

作者： Gan Xu Yun-Shu Cui Xue-Lian Jiang Cong-Qiao Xu Jun Li Xu-Dong Chen Jiangsu Collaborative Innovation Center of Biomedical functional Materials and Jiangsu Key Laboratory of New Power Batteries School of Chemistry and Materials Science Nanjing Normal University department of Chemistry and Guangdong Provincial Key Laboratory of Catalytic Chemistry Southern University of Science and Technology department of Chemistry and Engineering Research Center of Advanced Rare-Earth Materials of Ministry of Education Tsinghua University State Key Laboratory of Coordination Chemistry Nanjing University

Iron-metal clusters are crucial in a variety of critical biological and material systems,including metalloenzymes,catalysts,and magnetic storage devices.However,a synthetic high-nuclear iron cluster has been absent due to the extreme difficulty in stabilizing species with direct iron-iron bonding.In this work,we have synthesized,crystallized,and characterized a（Tp*）4W4S12(Fe@Fe12) cluster(Tp*=tris（3,5-dimethyl-1-pyrazolyl）borate（1-）),which features a rare trideca-nuclear,icosahedral[Fe@Fe12] cluster core with direct multicenter iron-iron bonding between the interstitial iron（Fei） and peripheral irons（Fep）,as well as Fep…Fepferromagnetic coupling.Quantum chemistry studies reveal that the stability of the cluster arises from the 18-electron shell-closing of the [Fe@Fe12]16+core,assisted by its bonding interactions with the peripheral tridentate [（Tp*）WS3]4-ligands which possess both S→Fe donation and spin-polarized Fe-Wσ bonds.The ground-state electron spin is theoretically predicted to be S=32/2 for the cluster.The existence of low oxidation-state（OS～+1.23） iron in this compound may find interesting applications in magnetic storage,spintronics,redox chemistry,and cluster catalysis.

关键词： Fe13 cluster iron-sulfur cluster low-valence iron iron−iron bond high spin complex

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