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Fluorescent carbon dots synthesized in solid phase and air for application in LEDs

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Nano Research 2024年第9期17卷 8495-8503页

作者： Wei-Jie Zheng zhao-Nan Sun Yi-Ming Wang huan-Ming Xiong Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan UniversityShanghai 200438China

Carbon dots(CDs)have been widely adopted as optical materials because of their excellent luminescent ***,most of the reported synthetic methods are conducted in solvents,especially hydrothermal/solvothermal reactions,leading to intractable problems such as toxic and flammable solvents,complex and inseparable by-products,and dangerously high pressures and ***-phase synthesis of CDs in air is an effective solution to overcome the above issues,but solid reactions always result in uncontrolled growth and agglomeration of *** this study,some inorganic salts are selected as catalysts for synthesizing CDs in solid states and air,which also play as dispersants to hinder CDs *** the meantime,some aromatic derivatives containing hydroxyl and amino groups are chosen as carbon sources,ground with the optimized catalyst,and then heated together in *** production yields are affected by the reaction time and reactant ratio,while the graphitization degrees of the CDs are determined by the reaction *** IG/ID value of their Raman spectra increases from 0.59 to 0.85,and the particle size decreases from 2.5 to 1.4 nm when the synthesis temperature is increased from 200 to 280℃.The as-prepared CDs show emission peaks ranging from 366 to 606 nm,with the photoluminescence(PL)quantum yield up to 53%.Their emission color variation mainly results from different carbon sources,which can be ascribed to the differences in the element composition,functional groups,and graphitic nitrogen content of these *** dispersing CDs of different concentrations into polyvinyl alcohol(PVA)and combining them with blue LEDs,cold,standard,and warm white light emitting devices(WLEDs)are prepared,with a color rendering index(CRI)up to *** the as-prepared CDs have antioxidant ability at high temperature,the as-prepared WLEDs have long lifespans,remaining the effective white luminescence after 72 h continuous work.

关键词： carbon dot solid-phase synthesis white LED photoluminescence inorganic salt catalysis

The evolving roles of Wnt signaling in stem cell proliferation and differentiation, the development of human diseases, and therapeutic opportunities

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Genes & Diseases 2024年第3期11卷 155-187页

作者： Michael Yu Kevin Qin Jiaming Fan Guozhi zhao Piao zhao Wei Zeng Connie Chen Annie Wang Yonghui Wang jiamin Zhong Yi Zhu William Wagstaff Rex C.haydon hue h.Luu Sherwin ho Michael J.Lee Jason Strelzow Russell R.Reid Tong-Chuan he School of Medicine Rosalind Franklin University of Medicine and ScienceNorth ChicagoIL 60064USA Molecular Oncology Laboratory Department of Orthopedic Surgery and Rehabilitation MedicineThe University of Chicago Medical CenterChicagoIL 60637USA Ministry of Education Key Laboratory of Diagnostic Medicine and Department of Clinical BiochemistryThe School of Laboratory MedicineChongqing Medical UniversityChongqing 400016China Department of Orthopedic Surgery The First Affliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Urology The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Clinical Laboratory Medicine Shanghai Jiaotong University School of MedicineShanghai 200000China Department of Orthopaedic Surgery Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China Laboratory of Craniofacial Suture Biology and Development Department of Surgery Section of Plastic SurgeryThe University of Chicago Medical CenterChicagoIL 60637USA Department of Neurology The First Dongguan Affiliated HospitalGuangdong Medical UniversityDongguanGuangdong 523475China

The evolutionarily conserved Wnt signaling pathway plays a central role in develop-ment and adult tissue homeostasis across *** proteins are secreted,lipid-modified signaling molecules that activate the canonical(β-catenin dependent)and non-canonical(β-catenin independent)Wnt signaling *** behaviors such as proliferation,differ-entiation,maturation,and proper body-axis specification are carried out by the canonical pathway,which is the best characterized of the known Wnt signaling *** signaling has emerged as an important factor in stem cell biology and is known to affect the self-renewal of stem cells in various *** includes but is not limited to embryonic,hematopoietic,mesenchymal,gut,neural,and epidermal stem *** signaling has also been implicated in tumor cells that exhibit stem cell-like *** signaling is crucial for bone formation and presents a potential target for the development of therapeutics for bone *** surprisingly,aberrant Wnt signaling is also associated with a wide variety of diseases,including *** of Wnt pathway members in cancer can lead to unchecked cell proliferation,epithelial-mesenchymal transition,and ***,advances in the understand-ing of dysregulated Wnt signaling in disease have paved the way for the development of novel therapeutics that target components of the Wnt *** with a brief overview of the mechanisms of canonical and non-canonical Wnt,this review aims to summarize the cur-rent knowledge of Wnt signaling in stem cells,aberrations to the Wnt pathway associated with diseases,and novel therapeutics targeting the Wnt pathway in preclinical and clinical studies.

关键词： β-Catenin Cancer Canonical Wnt Disease Non-canonical Wnt Stem cells Targeted therapy Wnt signaling

Effect of Artificial Cooling Extrusion on Microstructure and Mechanical Properties of Mg–Zn–Y Alloys

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1115-1127页

作者： Qi-Yu Liao Da-Zhi zhao Qi-Chi Le Wen-Xin hu Yan-Chao Jiang Wei-Yang Zhou Liang Ren Dan-Dan Li zhao-Yang Yin School of Materials Science and Engineering Northeastern UniversityShenyang110819China Key Laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang110819China Key Laboratory of Lightweight Structural Materials Liaoning ProvinceNortheastern UniversityShenyang110819China Baotou Research Institute of Rare Earths Baotou014000China

Microstructure and mechanical properties of Mg–Zn–Y alloys with different Zn/Y atomic ratios with or without artificial cooling (AC) extrusion were systematically investigated in this work. The results show that bimodal microstructure consisting of submicron dynamic recrystallized (DRXed) grains with high fraction of low-angle grain boundaries (LAGBs) and elongated unDRXed grains was formed in Mg_(98.7)Zn_(1)Y_(0.3) alloy with AC extrusion. The AC process effectively limits the growth of precipitated phases, and large amount of nanoscale precipitates were dynamically precipitated during the extrusion process. AC extrusion could effectually refine the lamellar 14h LPSO phases and inhibit the transition from stacking faults to LSPO phases in Mg_(98)Zn_(1)Y_(1) alloy and the narrow LPSO phase in Mg_(98)Zn_(1)Y_(1)-AC alloy which could promote the nucleation of DRXed grains. The AC extrusion significantly improves the strength of Mg–Zn–Y alloys. Owing to AC extrusion, the strength improvement of Mg_(98.7)Zn_(1)Y_(0.3) alloy is mainly attributed to fine grain strengthening, dislocation strengthening, and nano-phases precipitation strengthening. After AC process, more fine grains and nano-phases jointly strengthen the Mg_(98)Zn_(1)Y_(1) alloy. The Mg_(98)Zn_(1)Y_(1) alloy obtains optimal mechanical properties after extrusion at 623 K, with ultimate tensile strength (UTS) of 406 MPa, yield strength (YS) of 388 MPa, and elongation (EL) of 5.6%.

关键词： Mg-Zn-Y Artificial cooling Extrusion Microstructure Mechanical properties

Structure design and coordinated motion analysis of bionic crocodile robot

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Biomimetic Intelligence & Robotics 2024年第2期4卷 50-62页

作者： Jun Wang Jingya Zheng Yuhang zhao Kai Yang School of Information and Control Engineering China University of Mining and TechnologyXuzhou 221116China

Crocodiles,one of the oldest and most resilient species on Earth,have demonstrated remarkable locomotor abilities both on land and in water,evolving over millennia to adapt to diverse *** this study,we draw inspiration from crocodiles and design a highly biomimetic crocodile robot equipped with multiple degrees of freedom and articulated trunk *** design is based on comprehensive analysis of the structural and motion characteristics of real *** bionic crocodile robot has a problem of limb-torso incoordination during *** solve this problem,we used the D-h method for both forward and inverse kinematics analysis of the robot's legs and *** a series of simulation experiments,we investigated the robot's motion stability,fault tolerance,and adaptability to environments in two motor patterns:with and without spine and tail *** experimental results show that the bionic crocodile robot exhibits superior motion performance when the spine and tail cooperate with the *** study not only demonstrates the potential of biomimicry in robotics but also underscores the significance of understanding how nature's designs can inform and enhance technological innovations.

关键词： Bionic crocodile robot Kinematic modeling Motion simulation Multipart coordination

Modified electronic structure and enhanced hydroxyl adsorption make quaternary Pt-based nanosheets efficient anode electrocatalysts for formic acid-/alcohol-air fuel cells

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Journal of Energy Chemistry 2024年第5期92卷 142-150页

作者： Fengling zhao Qiang Yuan Siyang Nie Liang Wu Xun Wang State-Local Joint Laboratory for Comprehensive Utilization of Biomass Center for R&D of Fine ChemicalsCollege of Chemistry and Chemical EngineeringGuizhou UniversityGuiyang 550025GuizhouChina Key Lab of Organic Optoelectronics&Molecular Engineering Tsinghua UniversityBeijing 100084China School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Surface/interface engineering of a multimetallic nanostructure with diverse electrocatalytic properties for direct liquid fuel cells is desirable yet ***,using visible light,a class of quaternary Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)ultrathin nanosheets is fabricated and used as high-performance anode electrocatalysts for formic acid-/alcohol-air fuel *** modified electronic structure of Pt,enhanced hydroxyl adsorption,and abundant exterior defects afford Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)/C high intrinsic anodic electrocatalytic activity to boost the power densities of direct formic acid-/methanol-/ethanol-/ethylene glycol-/glycerol-air fuel cells,and the corresponding peak power density of Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)/C is respectively 129.7,142.3,105.4,124.3,and 128.0 mW cm^(-2),considerably outperforming Pt/*** in situ Fourier transform infrared reflection spectroscopy reveals that formic acid oxidation on Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)/C occurs via a CO_(2)-free direct *** functional theory calculations show that the presence of Ag,Bi,and Te in Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)suppresses CO^(*)formation while optimizing dehydrogenation steps and synergistic effect and modified Pt effectively enhance h_(2)O dissociation to improve electrocatalytic *** synthesis strategy can be extended to 43 other types of ultrathin multimetallic nanosheets(from ternary to octonary nanosheets),and efficiently capture precious metals(i.e.,Pd,Pt,Rh,Ru,Au,and Ag)from different water sources.

关键词： Pt-based nanosheets Modifiedelectronic structure Enhanced hydroxyl adsorption Formicacidand alcohol oxidation Direct liquid fuel cells

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Protein neddylation and its role in health and diseases

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1869-1904页

作者： Shizhen Zhang Qing Yu Zhijian Li Yongchao zhao Yi Sun Department of Breast Surgery the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310029China Cancer Institute(Key Laboratory of Cancer Prevention and Intervention China National Ministry of Education)the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310029China Institute of Translational Medicine Zhejiang University School of MedicineHangzhou 310029China Department of Thyroid Surgery Zhejiang Cancer HospitalInstitute of Basic Medicine and Cancer(IBMC)Chinese Academy of SciencesHangzhou 310022China Key Laboratory of head&Neck Cancer Translational Research of Zhejiang Province Hangzhou 310022China Department of hepatobiliary and Pancreatic Surgery Zhejiang University School of MedicineHangzhou 310029China Zhejiang Provincial Key Laboratory of Pancreatic Disease The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310029China Zhejiang University Cancer Center Hangzhou 310029China Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang Hangzhou 310024China Research Center for Life Science and human health Binjiang Institute of Zhejiang UniversityHangzhou 310053China

NEDD8(Neural precursor cell expressed developmentally downregulated protein 8)is an ubiquitin-like protein that is covalently attached to a lysine residue of a protein substrate through a process known as neddylation,catalyzed by the enzyme cascade,namely NEDD8 activating enzyme(E1),NEDD8 conjugating enzyme(E2),and NEDD8 ligase(E3).The substrates of neddylation are categorized into cullins and non-cullin *** of cullins activates CRLs(cullin RING ligases),the largest family of E3 ligases,whereas neddylation of non-cullin substrates alters their stability and activity,as well as subcellular ***,the neddylation pathway and/or many neddylation substrates are abnormally activated or over-expressed in various human diseases,such as metabolic disorders,liver dysfunction,neurodegenerative disorders,and cancers,among ***,targeting neddylation becomes an attractive strategy for the treatment of these *** this review,we first provide a general introduction on the neddylation cascade,its biochemical process and regulation,and the crystal structures of neddylation enzymes in complex with cullin substrates;then discuss how neddylation governs various key biological processes via the modification of cullins and non-cullin *** further review the literature data on dysregulated neddylation in several human diseases,particularly cancer,followed by an outline of current efforts in the discovery of small molecule inhibitors of neddylation as a promising therapeutic ***,few perspectives were proposed for extensive future investigations.

关键词： NEDD8 attached attractive

Synergistic asymmetric diarylation of tethered alkenes via C–h functionalization of simple(hetero)arenes

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Science China Chemistry 2024年第8期67卷 2710-2718页

作者： Jian Yao Can zhao Lili Shao Xiaohong huo Xiaoming Wang Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Frontiers Science Center for Transformative MoleculesSchool of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Organometallic Chemistry and Shanghai hongkong Joint Laboratory in Chemical Synthesis Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China

By virtue of the atom-and step-economy, utilization of simple arenes as a supplant of pre-prepared aryl metal species or aryl halides for the synthesis of arylated chiral molecules has attracted great attention from the synthetic community. While transition-metal-catalyzed enantioselective diarylation of tethered alkenes has been employed to prepare important chiral cyclic compounds, the direct use of simple arenes as aryl precursors is still underdeveloped, probably due to the difficulties in the effective control of the reactivity, site-selectivity and/or enantioselectivity. herein we report an asymmetric Pd/Ag dual metal catalytic system for the non-directed, site-and enantioselective domino heck/intermolecular C–h functionalization of *** studies showed that Pd and Ag act in cooperation in the catalysis and the chiral bisphosphine ligand plays a bifunctional role, i.e., assisting the silver species in the cleavage of the aryl C–h bond, while inducing the enantioselectivity on direct complexation with palladium. This method provides an efficient approach to the corresponding chiral oxindoles with good enantiomeric excesses from a broad scope of arenes, including fluoroarenes, heteroarenes and several complex products derived from medicines or natural products.

关键词： asymmetric Pd/Ag dual metal catalytic system simple arenes C–h functionalization bifunctional role chiral oxindoles

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FaultMonitoring Strategy for PV System Based on I-V Feature Library

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Energy Engineering 2024年第3期121卷 643-660页

作者： huaxing zhao Yanbo Che Gang Wen Yijing Chen School of Electrical and Information Engineering Tianjin UniversityTianjin300000China State Grid Shuozhou Electric Power Supply Company Shuozhou036000China China huaneng Clean Energy Research lnstitute Technology Co. Ltd.Beijing102209China

Long-term use in challenging natural conditions is possible for photovoltaic modules,which are extremely prone to *** to diagnose and address faults in Photovoltaic(PV)power systems in a timely manner can cause permanent damage to PV modules and,in more serious cases,***,research into photovoltaic module defect detection techniques is crucial for the growth of the photovoltaic sector as well as for maintaining national economic prosperity and ensuring public *** the drawbacks of the current real-time and historical data-based methods for monitoring distributed PV systems,this paper proposes a method for monitoring PV systems at the module or string level that can be achieved by monitoring only electrical *** approach doesn’t need a lot of tests to get the operational data of PV modules beforehand and only requires theoretical feature libraries of PV modules through panel parameter *** present operating conditions and the open-circuit and short-circuit faults can be precisely identified by comparing the observed open-circuit voltage and short-circuit current with the corresponding data in the theoretical feature *** that,by comparing the measured maximum power point voltage and current with the corresponding data in the theoretical feature library through the threshold method,aging and shadowing faults can be accurately *** testing was done to see whether the suggested method was *** results show that the proposed technique is able to diagnose open-circuit faults,short-circuit faults,aging faults,and shadowing faults with shadow occlusion above 20%.

关键词： PV system lambert W function threshold method

The influence of silica on reaction rates and molecular hydrogen(h_(2))generation during olivine hydrothermal alteration

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Science China Earth Sciences 2024年第1期67卷 222-233页

作者： Ruifang hUANG Weidong SUN Xing DING Yusheng zhao Yibing LI Xiuqi ShANG CAS Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China SUSTech Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen 518055China Center of Deep Sea Research Institute of OceanologyChinese Academy of SciencesQingdao 266071China State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Institue of Geology Chinese Academy of Geological SciencesBeijing 100037China

hydrothermal alteration of olivine greatly influences geodynamics and the recycling of volatiles(such as water and carbon)in subduction *** is an important component of geological fluids,and its influence on the hydrothermal alteration of olivine remains poorly *** this study,we performed experiments at 300–515℃ and 3.0 kbar(1 bar=10^(5)Pa)by reacting well homogenized mixtures of olivine and silica powders with saline solutions(0.5 mol L^(−1)NaCl).Silica greatly influences the reaction pathways,reaction rates,and molecular hydrogen(h_(2))formation during olivine hydrothermal *** experiments at 300℃ and 3.0 kbar with mixtures of olivine and 10 wt%silica,olivine was replaced by serpentine and *** proportions of serpentine and talc were determined according to standard curves based on infrared spectroscopy *** 6.5%serpentine and 12%talc were produced after an experimental duration of 7 days,which had no change after a longer period(14 days).Compared to the kinetics in silica-free systems,the rates of olivine hydrothermal alteration in experiments with 10 wt%silica are much *** overall reaction is:4.5Forsterite+5.5SiO_(2),aq+4h_(2)O=Serpentine+*** the addition of more silica(20 wt%and 40 wt%),olivine was transformed into *** rates of reaction were much faster,e.g.,for experiments with olivine and 20 wt%silica,43%of talc was produced after 14 days,which increased to 77%for experiments with 40 wt%silica over the same *** overall reaction is:3Forsterite+5SiO_(2),aq+2h_(2)O=*** experiments at 400–505℃ and 3.0 kbar,the promoting effect of silica on olivine hydrothermal alteration was also observed,which is closely associated with a decrease in Gibbs free energies of olivine hydrothermal *** 300℃ and 3.0 kbar,silica decreased h_(2)formed during olivine hydrothermal alteration by around an order of magnitude,resulting in an increase in oxygen *** on measured h_(2),we calibrated ox

关键词： Olivine hydrothermal alteration Silica Serpentinization hydrogen Serpentine

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