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In-situ fabricated anisotropic halide perovskite nanocrystals in polyvinylalcohol nanofibers: Shape tuning and polarized emission

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Nano Research 2019年第6期12卷 1411-1416页

作者： Linghai meng Changgang Yang jingjia meng Yongzhi Wang Yong Ge Ziqiang Shao Guofeng Zhang Andrey L.Rogach Haizheng Zhong Beijing Key Laboratory of Nanophotonics and Ultrafine Optoelectronic Systems School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Engineering Research Center of Cellulose and Its Derivatives School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing H 100081China State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Laser SpectroscopyShanxi UniversityTaiyuan 030006China Department of Materials Science and Engineering and Centre for Functional Photonics (CFP)City University of Hong KongHong Kong 999077China

We report an in-situ fabrication of halide perovskite (CH3NH3PbX3,CH3NH3 =methylammonium,MA,X =Cl,Br,I) nanocrystals in polyvinylalcohol (PVA) nanofibers (MAPbX3@PVA nanofibers) through electrospinning a perovskite precursor *** the content of the precursors increased,the resulting MAPbBr3 nanocrystals in PVA matrix changed the shape from ellipsoidal to pearl-like,and finely into *** MAPbBr3@PVA nanofibers show strong polarized emission with the photoluminescence quantum yield of up to 72%.We reveal correlations between the shape of in-situ fabricated perovskite nanocrystals and the polarization degree of their emission by comparing experimental data from the single nanofiber measurements with theoretical *** emission of MAPbBr3@PVA nanofibers can be attributed to the dielectric confinement and quantum confinement ***,nanofibers can be efficiently aligned by using parallel positioned conductor strips with an air gap as collector.A polarization ratio of 0.42 was achieved for the films of well-aligned MAPbBr3@PVA nanofibers with a macroscale size of 0.5 cm × 2 cm,which allows potential applications in displays,lasers,waveguides,etc.

关键词： lead halide perovskite nanofibers electrospinning anisotropy polarized emission

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Impact of ocean data assimilation on the seasonal forecast of the 2014/15 marine heatwave in the Northeast Pacific Ocean

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 24-31页

作者： Tiantian Tang Jiaying He Huihang Sun jingjia Luo Institute for Climate and Application Research(ICAR)/Key Laboratory of Meteorological Disaster Nanjing University of Information Science and TechnologyNanjingChina

A remarkable marine heatwave,known as the“Blob”,occurred in the Northeast Pacific Ocean from late 2013 to early 2016,which displayed strong warm anomalies extending from the surface to a depth of 300 *** study employed two assimilation schemes based on the global Climate Forecast System of Nanjing University of Information Science(NUIST-CFS 1.0)to investigate the impact of ocean data assimilation on the seasonal prediction of this extreme marine *** sea surface temperature(SST)nudging scheme assimilates SST only,while the deterministic ensemble Kalman filter(EnKF)scheme assimilates observations from the surface to the deep *** latter notably improves the forecasting skill for subsurface temperature anomalies,especially at the depth of 100-300 m(the lower layer),outperforming the SST nudging *** excels in predicting both horizontal and vertical heat transport in the lower layer,contributing to improved forecasts of the lower-layer warming during the *** improvements stem from the assimilation of subsurface observational data,which are important in predicting the upper-ocean *** results suggest that assimilating ocean data with the EnKF scheme significantly enhances the accuracy in predicting subsurface temperature anomalies during the Blob and offers better understanding of its underlying mechanisms.

关键词： Seasonal forecast Ocean data assimilation Marine heatwave Subsurface temperature

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钙钛矿二维纳米材料的合成和发光研究进展

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应用化学 2018年第3期35卷 342-350页

作者：孟竞佳张峰任艳东刘立格刘永皓钟海政北京理工大学材料学院纳米光子学与超精密光电重点实验室北京100081 大庆师范学院机电工程学院黑龙江大庆163721

钙钛矿纳米材料的研究取得了飞速发展:一方面,合成方法不断涌现,已经可以实现从零维纳米晶、一维纳米线到二维纳米片的形貌精确控制,对其尺寸和维度依赖的光学性质认识也不断深入;另一方面,钙钛矿纳米材料的光学和光电子应用也得到了快... 详细信息

钙钛矿纳米材料的研究取得了飞速发展:一方面,合成方法不断涌现,已经可以实现从零维纳米晶、一维纳米线到二维纳米片的形貌精确控制,对其尺寸和维度依赖的光学性质认识也不断深入;另一方面,钙钛矿纳米材料的光学和光电子应用也得到了快速发展,其中,基于钙钛矿量子点的光致发光和电致发光技术最受关注。由于钙钛矿的天然层状结构,通过配体调控很容易制备出二维纳米材料,其发光性能可以通过层数和组分进行调节,最高量子产率超过85%,且具有偏振发光特性,有望成为一类新型发光材料。本文从制备方法、光致发光和电致发光应用等方面综述了基于钙钛矿二维纳米材料的进展,并对其未来的发展方向进行讨论。

关键词：二维纳米材料钙钛矿量子限域效应发光

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Numerical analysis of deflection control of a gas plasma jet based on magnetohydrodynamic staggered electrode configuration

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Chinese Journal of Aeronautics 2022年第12期35卷 47-58页

作者： jingjia ZHANG Junwei LI Zelin ZHANG Zhijun WEI School of Aerospace Beijing Institute of TechnologyBeijing 100081China

To control the deflection of the gas plasma jet, a new analytical method is proposed based on the Magnetohydrodynamic(MHD) technique. Based on the typical MHD power generation model, the applied voltage is applied to the staggered electrodes, that is, a pair of electrodes on the same side wall are connected to generate an axial current in the channel. Under the action of the magnetic field perpendicular to the direction of the flow, the plasma is subjected to electromagnetic forces perpendicular to these two directions, and the jet is deflected. The computational model including the Navier-Stokes equations coupled with electromagnetic source terms, the electric potential equation and Ohm’s law is solved. The deflection of the gas jet under the action of an electromagnetic field is observed, and the maximum deflection angle is about 14.8°. The influences of the electric field, magnetic field, and conductivity on the jet deflection are studied. Results show that although the influences of these three factors on the deflection are similar, and the effect of increasing the electric field strength is slightly greater, priority should be given to increasing the magnetic field strength from the perspective of reducing energy consumption. The Stuart number is introduced to assess the ability of electromagnetic force to control jet deflection. When the electromagnetic parameters are constant, this solution provides better control of low-density and low-speed fluid flows. The calculation results show that using the staggered electrode method configuration is feasible in terms of controlling the deflection of a plasma jet deflection.

关键词： Deflection angle Deflection control Gas plasma Magnetohydrodynamic Thrust vector

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Interdecadal Variations of ENSO Impacts over the Indo-Northwest Pacific Region and the Related Mechanisms

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Journal of Meteorological Research 2024年第2期38卷 235-248页

作者： Hongxia LAN Jing MA Haiming XU jingjia LUO Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)/Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change(KLME/ILCEC)Nanjing University of Information Science&TechnologyNanjing 210044 School of Atmospheric Sciences Nanjing University of Information Science&TechnologyNanjing 210044

Owing to limited observations,it remains unknown whether the impact of El Niño-Southern Oscillation(ENSO)on the Indian Ocean-Northwest Pacific(IO-NWP)climate showed decadal changes in the early 20th *** multi-source reanalysis and hindcast datasets from the ECMWF and NOAA extending back to 1901,this study investigates interdecadal variations of the impact of ENSO on the IO-NWP climate from 1901 to *** is found that the influence of ENSO on the IO-NWP climate shows“strong-weak-strong”interdecadal change during *** is characterized by much weaker Indian Ocean sea surface temperature(SST)warming and a weaker NWP subtropical anticyclone(NWPSA)in the following summer of El Ni?o during 1946-1967,compared with those in the other two periods(1901-1945 and 1968-2009).Analyses of the datasets indicate that the interdecadal variation is mainly associated with the change in ENSO *** contrast to the period of 1946-1967,a greater SST variance occurred in the central-eastern equatorial Pacific during 1901-1945 and 1968-2009.A stronger El Ni?o tends to generate more significant anticyclonic anomalies over the southeast Indian Ocean through *** northwesterly anomalies to the south of the anticyclone weaken the southeast trade winds and warm the south Indian Ocean SST via wind-evaporation-SST feedback,and the positive south Indian Ocean SST anomalies trigger westward-propagating oceanic Rossby waves to induce stronger warming of the southwest Indian Ocean,leading to a significant asymmetric wind pattern across the equator in *** profound northeastward winds on the north side weaken the southwest monsoon,leading to a“second warming”over the north Indian Ocean in summer,which anchors the eastward-propagating warm Kelvin waves and results in a stronger NWPSA by inducing surface divergence and suppressing deep convection.

关键词： ENSO Indo-Northwest Pacific Northwest Pacific subtropical anticyclone decadal changes

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Immobilization of Glucose Oxidase on Ordered Macroporous Silicas Functionalized with Amino Group

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Chinese Journal of Chemistry 2012年第2期30卷 283-287页

作者： Wu,Quanzhou He,Jianfeng Zhang,jingjia Ou,Jiming College of Chinese Materia Medica Guangzhou University of Chinese MedicineGuangzhouGuangdong 510006China

A novel glucose oxidase immobilized on three-dimensionally ordered macroporous （3DOM） material has been prepared by firstly preparation of hybrid 3DOM SiO2-NH2 materials using colloidal crystal method, and following covalent immobilization of glucose oxidase on the pore walls of the 3DOM materials. The materials were characterized by SEM, FTIR, DSC and BET techniques. SEM observation shows that the macropores are highly ordered and are interconnected by small windows. FTIR measurement shows that there are amino and organic groups in the pore walls. The surface area of the 3DOM SiO2-NH2 material is about 10.2 m2/g. The loaded amount of enzyme is increased with amino content in the materials. The immobilized enzyme has high activity, thermal stability and can be reused.

关键词： three-dimensionally ordered macropore SiO2 glucose oxidase supported catalyst materials science

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Effectiveness of Monetary Policy in China: Evidence from Factor-Augmented Vector Autoregression Model

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Frontiers of Economics in China-Selected Publications from Chinese Universities 2019年第3期14卷 336-370页

作者： Yunpeng Sun jingjia Zhang Zhang School of Economics Tianjin University of CommerceTianjin 300134China APEC Study Center Nankai UniversityTianjin 300071China Collaborative Innovation Center for China Economy Nankai UniversityTianjin 300071China

Since 2002,the People's Bank of China has frequently used both quantity-based direct monetary instruments and price-based indirect monetary instruments to promote economic growth and stabilize price ***,this study estimates 13 three-variable factor-augmented vector autoregression (FAVAR) models to explore how two types of monetary instruments affect China's economy and price ***,we find that monetary policy has positive effects on China's economy and price ***,this study clearly states that the effectiveness of China's monetary policy on the economy has depended on China's quantity-based direct monetary instruments since ***,the effectiveness of quantity-based direct monetary instruments on China's economy and price level is dependent on the significant and positive effects of quantity-based direct monetary instruments after the 2008 financial ***,the significant and positive effects of price-based indirect monetary instruments on China's economy and price level before 2008 cannot fundamentally change their current insignificant effects on China's economy and price level.

关键词： China's monetary policy quantity-based direct instruments price-based indirect instruments factor-augmented vector autoregression model (FAVAR)

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A Critique of Investment Protection of China’s Multinational Enterprises in Host ASEAN Nations – A Survey of the Legal Requisites for Foreign Investors of Guangdong Corporations in Southeast Asian Nations

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Proceedings of Business and Economic Studies 2019年第1期2卷 1-10页

作者： jingjia Ke Guangdong University of Finance and Economics GuangdongP.R.510320

As a result of the development of the“One Belt One Road”and“Stepping-out”strategy for multinational enterprises,China’s outward directed investments have grown *** the transformation period from a capital-importing country to a capital-exporting country,issues of insufficient investment protection laws on China’s outward investment have *** examine major investment risks,investment dispute settlement mechanisms,and legal barriers of China’s multinational enterprises in ASEAN States,this study selects typical state-owned enterprises and private companies among 300 Guangdong businesses,which invested in ASEAN via data analyses,surveys,and field *** findings of this research provide a reference for the investment protection and for the launching of investment litigation of these Chinese multinational enterprises whenever it is required.

关键词： investment ASEAN features and implications dispute settlement promotion and facilitation

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Underestimated relationship between westerly wind bursts and ENSO in CMIP6 models

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Atmospheric and Oceanic Science Letters 2023年第6期16卷 16-21页

作者： Mingjie Wang Chaoxia Yuan Jingchan Liu Yihua Wei Jiye Wu jingjia Luo Key Laboratory of Meteorological Disaster of Ministry of Education Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersInstitute for Climate and Application Research(ICAR)Nanjing University of Information Science&TechnologyNanjing China

观测表明,热带太平洋的西风爆发(WWBs)在厄尔尼诺南方涛动(ENSO)的发生,发展和多样性中起着关键作用.因此,在耦合模式中真实地再现WWBs对于改进ENSO的模拟和预测有重要意义.在本研究中,作者发现CMIP6的耦合模式的集合平均能很好地再现... 详细信息

观测表明,热带太平洋的西风爆发(WWBs)在厄尔尼诺南方涛动(ENSO)的发生,发展和多样性中起着关键作用.因此,在耦合模式中真实地再现WWBs对于改进ENSO的模拟和预测有重要意义.在本研究中,作者发现CMIP6的耦合模式的集合平均能很好地再现了热带太平洋WWB发生频率的纬向分布及其年际变动.然而,大多数CMIP6模型极大低估了WWB和ENSO的线性关系.这可能是因为大多数CMIP6模式里海气耦合强度低于观测:海气耦合强度与WWB-ENSO关系的模式间相关系数高达0.91.

关键词：西风爆发 ENSO CMIP6模式

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De Novo Design of a Highly Stable Ovoid TIM Barrel:Unlocking Pocket Shape towards Functional Design

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BioDesign Research 2022年第1期2022卷 68-80页

作者： Alexander E.Chu Daniel Fernandez jingjia Liu Raphael R.Eguchi Po-Ssu Huang Biophysics Program Stanford UniversityStanfordCAUSA Department of Bioengineering Stanford UniversityStanfordCAUSA Program in Chemistry EngineeringAnd Medicine for Human Health(ChEM-H)Stanford UniversityStanfordCAUSA Stanford ChEM-H Macromolecular Structure Knowledge CenterStanford UniversityStanfordCAUSA Department of Biochemistry Stanford UniversityStanfordCAUSA Bio-X Institute Stanford UniversityStanfordCAUSA

The ability to finely control the structure of protein folds is an important prerequisite to functional protein design. The TIM barrelfold is an important target for these efforts as it is highly enriched for diverse functions in nature. Although a TIM barrel proteinhas been designed de novo, the ability to finely alter the curvature of the central beta barrel and the overall architecture of the foldremains elusive, limiting its utility for functional design. Here, we report the de novo design of a TIM barrel with ovoid (twofold)symmetry, drawing inspiration from natural beta and TIM barrels with ovoid curvature. We use an autoregressive backbonesampling strategy to implement our hypothesis for elongated barrel curvature, followed by an iterative enrichment sequencedesign protocol to obtain sequences which yield a high proportion of successfully folding designs. Designed sequences arehighly stable and fold to the designed barrel curvature as determined by a 2.1Å resolution crystal structure. The designs showrobustness to drastic mutations, retaining high melting temperatures even when multiple charged residues are buried in thehydrophobic core or when the hydrophobic core is ablated to alanine. As a scaffold with a greater capacity for hosting diversehydrogen bonding networks and installation of binding pockets or active sites, the ovoid TIM barrel represents a major steptowards the de novo design of functional TIM barrels.

关键词： structure curvature backbone

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