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Investigation progresses of rare earth complexes as emitters or sensitizers in organic light-emitting diodes

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Light(Science & Applications) 2022年第7期11卷 1397-1413页

作者： Shuaibing Li liang zhou Hongjie Zhang State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of Sciences130022 ChangchunChina University of Science and Technology of China 230027 HefeiChina Department of Chemistry Tsinghua University100084 BeijingChina

Due to unique photo-physical characteristics,rare earth(RE)complexes play important roles in many fields,for example,telecommunications,life science,and organic light-emitting diodes(OLEDs).Especially,thanks to narrow emission bandwidth and 100%theoretical internal quantum efficiency(IQE),the study of RE complexes in the electroluminescence field has been a hot research topic in recent 30 *** a leading technology in solid-state light source fields,OLEDs have attracted great interest from academic researchers and commercial *** the last decades,OLED-based products have trickled into the commercial market and developed quickly into portable display ***,we briefly introduce the luminescent characteristics and electroluminescent(EL)study of RE complexes in material synthesis and device ***,we emphatically reveal the innovative application of RE complexes as sensitizers in *** experimental validation,the application of RE complexes as sensitizers can realize the complementary advantages of RE complexes and transition metal complexes,leading to significantly improved performances of *** application of RE complexes as sensitizers provides a new strategy for designing and developing novel high performances OLEDs.

关键词： complexes rare earth

Chaotic Motions of the van der Pol-Duffing Oscillator Subjected to Periodic External and Parametric Excitations with Delayed Feedbacks

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Acta Mathematicae Applicatae Sinica 2024年第4期40卷 1111-1126页

作者： liang-qiang zhou Fang-qi CHEN School of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Chaotic dynamics of the van der Pol-Duffing oscillator subjected to periodic external and parametric excitations with delayed feedbacks are investigated both analytically and numerically in this *** the Melnikov method,the critical value of chaos arising from homoclinic or heteroclinic intersections is derived *** feature of the critical curves separating chaotic and non-chaotic regions on the excitation frequency and the time delay is investigated analytically in *** monotonicity of the critical value to the excitation frequency and time delay is obtained *** is presented that there may exist a special frequency for this *** this frequency,chaos in the sense of Melnikov may not occur for any excitation *** also exists a uncontrollable time delay with which chaos always occurs for this *** simulations are carried out to verify the chaos threshold obtained by the analytical method.

关键词： Van der Pol-Duffing oscillator time delay chaos parametric excitation Melnikov method

Integrating the ecosystem service in sustainable plateau spatial planning:A case study of the Yarlung Zangbo River Basin

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Journal of Geographical Sciences 2021年第2期31卷 281-297页

作者： CHE Lei zhou liang XU Jiangang School of Architecture and Urban Planning Nanjing UniversityNanjing 210093China Faculty of Geomatics Lanzhou Jiaotong UniversityLanzhou 730070China Institute of Geographic Sciences and Natural Resources Research CASBeijing 100101China

The Yarlung Zangbo River Basin(YZRB)is a key ecological protection area on the Qinghai-Tibet Plateau(QTP).Determination of the ecosystem service values(ESVs)can help recognize the benefits of sustainable *** is gradually becoming the main path that constructs plateau spatial planning of integrating ecological protection,and achieves global sustainable development goals(SDGs)in *** this paper,the spatio-temporal dynamic evolutions of the ESVs were estimated on the multiple scales of“basin,subbasin and watershed”from 1980 to *** main factors influencing ESVs were explored in terms of physical geography,human activities,and climate *** had been proposed that sustainable spatial planning including ecological protection,basin management,and regional development was urgent to set *** results show that the increase in wetland and forest and results in an increase of 9.4%in the *** should be paid to the reduction of water and *** conservation(WC),waste treatment(WT),and soil formation and conservation(SFC)are the most important ecosystem services in the *** present,the primary problem is to solve the ESVs decreasing caused by glacier melting,grassland degradation,and desertification in the upper reaches *** middle reaches should raise the level of supply *** services should be increased in the lower reaches region on the premise of protecting *** ESVs in adjacent watersheds are interrelated and the phenomenon of“high agglomeration and low agglomeration”is obvious,existing hot-spots and cold-spots of ***,when the altitude is 4500-5500 m,the temperature is 3-8°C,and the annual precipitation is 350-650 mm,ESVs could reach its maximum.A framework of sustainable plateau spatial planning could provide references to delimit the ecological protection red line,key ecological function zone,and natural resource asset accounting on the QTP.

关键词： ecosystem service values spatial planning ecological protection Yarlung Zangbo River Basin Qinghai-Tibet Plateau

Numerical simulation and optimized design of cased telescoped ammunition interior ballistic

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Defence Technology（防务技术） 2018年第2期14卷 119-125页

作者： Jia-gang Wang Yong-gang Yu liang-liang zhou Rui Ye School of Energy and Power Engineering Nanjing University of Science and Technology Chongqing Wangjiang Industry Co. Ltd

In order to achieve the optimized design of a cased telescoped ammunition(CTA) interior ballistic design,a genetic algorithm was introduced into the optimal design of CTA interior ballistics with coupling the CTA interior ballistic model. Aiming at the interior ballistic characteristics of a CTA gun, the goal of CTA interior ballistic design is to obtain a projectile velocity as large as possible. The optimal design of CTA interior ballistic is carried out using a genetic algorithm by setting peak pressure, changing the chamber volume and gun powder charge density. A numerical simulation of interior ballistics based on a 35 mm CTA firing experimental scheme was conducted and then the genetic algorithm was used for numerical optimization. The projectile muzzle velocity of the optimized scheme is increased from 1168 m/s for the initial experimental scheme to 1182 m/s. Then four optimization schemes were obtained with several independent optimization processes. The schemes were compared with each other and the difference between these schemes is small. The peak pressure and muzzle velocity of these schemes are almost the same. The result shows that the genetic algorithm is effective in the optimal design of the CTA interior ballistics. This work will be lay the foundation for further CTA interior ballistic design.

关键词： Cased telescoped ammunition Interior ballistics Gunpowder Optimization genetic algorithm

Massive Particles' de Sitter Tunneling in (3+1)-Dimensional de Sitter Spacetimes

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Communications in Theoretical Physics 2008年第11期50卷 1258-1260页

作者： zhou liang ZHANG Jing-Yi Center for Astrophysics Guangzhou University Guangzhou 510006 China

In this paper,massive particles' Hawking radiation via tunneling from cosmological horizon of a(3+1)-dimensional de Sitter spacetime is *** to Parikh's theory,when a particle tunnels across the cos-mological horizon,the effective geometry is Schwarzschild-de Sitter *** this effective spacetime,a massiveparticle can be treated as a de Broglie *** method is *** emission spectrum is obtained,and it takesthe same functional form as that of massless particles.

关键词： black hole Hawking radiation quantum theory

Microstructure and properties of W-4.9Ni-2.1Fe heavy alloy with Dy2O3 addition

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Rare Metals 2019年第8期38卷 746-753页

作者： Yuan-Feng Xie liang-liang zhou Xiao-Yong Zhang Xiao-Xian Li Zeng-Lin zhou Xue-Hui Zhang Institute of Engineering and Technology General Research Institute for Nonferrous Metals Beijing 100088China School of Materials Science and Engineering Jiangxi University of Science and Technology Ganzhou 341000China

The W-4.9 Ni-2.1 Fe-xDy2 O3 heavy alloy was fabricated by high-energy ball milling and spark plasma sintering(SPS)technique,and the microstructure,mechanical and friction behavior and anti-corrosion ability were investigated by scanning electron microscope(SEM),Rockwell hardness tester,X-ray diffraction(XRD),reciprocating friction and wear tester,electrochemical station,*** results show that the trace Dy2 O3 particles,which mainly distributes in the W-M(tungsten-matrix)interface and the tungsten matrix phase,can dramatically decrease the tungsten grain size and the amount of O and P impurities aggregating in the interface,promote the γ-(Ni,Fe)bonding phase and tungsten particles uniform distribution,and increase the relative density,hardness,and wear and corrosion resistance *** the excessive Dy2 O3 addition can make the inhibition effect weaken,resulting in the decrease in the comprehensive performances of the ***,the amount of Dy2 O3 should be *** the adding amount of Dy2 O3 particles is 0.7 wt%,the comprehensive performances of the heavy alloy are the best.

关键词： Dysprosium oxide W-4.9Ni-2.1Fe alloy Spark plasma sintering Mechanical property Anticorrosion ability

FLUID DYNAMIC PERFORMANCE OF GROOVED PLANING BOAT AND ITS EFFECT ON RESISTANCE

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Journal of Hydrodynamics 2005年第5期17卷 571-579页

作者： SHI Zhong-kun WU Fang-liang zhou Feng College of Traffic Science and Engineering Huazhong University of Science and Technology Wuhan430074 China

In this paper, the fluid dynamic performance for a new boat form grooved planing boats is analyzed, and the results of resistance tests for seven grooved planing boat models of different types are presented in the form of curves of attack angle and resistance-weight ratio versus Froude number. According to these curves, the effect of some parameters of the boat type on the resistance is analyzed.

关键词： grooved planing boat fluid dynamic performanee resistanee

LADA strategy for the synthesis of unnatural amino acids and direct modifications of peptides

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Science China Chemistry 2023年第6期66卷 1788-1794页

作者： Jun-liang zhou Yun-Qi Liu Zhan-Kui Sun Shanghai Frontiers Science Center for Drug Target Identification and Drug Delivery School of Pharmaceutical SciencesShanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Pharm-X CenterSchool of Pharmaceutical SciencesShanghai Jiao Tong UniversityShanghai 200240China AI Pharma Center Zhangjiang Institute for Advanced StudyShanghai Jiao Tong UniversityShanghai 200240China Shanghai Artificial Intelligence Laboratory Shanghai 200232China

Unnatural amino acids(UAAs)are important building blocks in organic synthesis and drug *** are also frequently integrated into peptides or proteins for biological ***,the direct and simplified synthesis of UAAs remains a great *** the same time,vast known peptide modifications are based on carbon-heteroatom *** are no general methods for peptide modifications via the construction of C–C *** address this challenge,herein we propose the LADA strategy,which is composed of two steps:the selective labeling and activation of cysteine residues,the desulfurization to generate carbon-centered radical and the radical addition to alkenes to build C–C *** one-pot protocol has obvious advantages such as good functional group tolerance,biocompatible reaction conditions,and retained *** strategy was successfully utilized for the synthesis of unnatural amino acids and direct modifications of peptides.

关键词： unnatural amino acids peptide modifications desulfurization cysteine radical addition

Molecular characterization and gene functional analysis of Dicer-2 gene from Nilaparvata lugens （Hemiptera： Geometroidea）

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Insect Science 2013年第1期20卷 61-68页

作者： Xiao-Yi Zhang Kai Lu Jia-liang zhou Qiang zhou State Key Laboratory of Biological Control and Institute of Entomology Sun Yat-sen University Guangzhou China

Nilaparvata lugens （St^il）（Hemiptera： Geometroidea）, a serious rice pest in many countries of Asia, causes a great loss in rice production every year. RNA interference （RNAi） is a powerful technology for gene fimction study in insects and a potential tool for pest control. As a core component of RNAi pathway, Dicer-2 （Dcr-2） protein determines the production of small interfering RNA （siRNA） and is crucial for the efficiency of RNAi. In this study, the full-length complementary DNA （cDNA） ofN. lugens Dcr-2 （NlDcr-2） was first cloned and analyzed, and then the RNAi experiment was conducted to explore the function ofNlDcr-2 gene. The complete Dcv-2 cDNA ofN. lugens was 4 971 bp in length with an open reading frame （ORF） of 1,656 amino acids. Phylogenetic and protein domain analysis showed that the predicted N1Dcr-2 protein was similar to Tribolium castaneum. In the RNAi experiment, the messenger RNA level of NlDcr-2 was significantly reduced by NlDcr-2 double-stranded RNA （dsRNA）（dsDcr-2）. Fifty-five per cent decrease of N1Dcr-2 was found after 4 days of unremitting feeding. No significant effect was observed on the development ofN. lugens after dsRNA ingestion.

关键词： clone Dicer-2 Nilaparvata lugens RNAi qRT-PCR