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Development of a novel Eu^(3+)-doped tantalate red-emitting phosphor for w-LEDs application

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Journal of Rare Earths 2024年第8期42卷 1479-1488,I0003页

作者： fan Zeng Jingjing ru Bing Zhao Feiyun Guo Jianzhong Chen College of Chemistry and Materials Fujian Province University Key Laboratory of Green Energy and Environment CatalysisNingde Normal University.Ningde352100China School of Environment and Resources School of Carbon Neutral and Modern IndustryFujian Normal UniversityFuzhou350007China College of Information and Mechanical&Electrical Engineering Ningde Normal UniversityNingde352100China College of Chemistry Fuzhou UniversityFuzhou350108China

Two novel phosphors LiBa_(4(1-x))Eu_(4x)Ta_(3)O_(12)(H-LBTO:xEu^(3+)) and Li_(0.25)Ba_(1-x)Eu_(x)Ta_(0.75)O_(3)(C-LBTO:xEu^(3+))were prepared successfully by a molten salt *** transformation between these two structures was realized by changing the sintering temperature or changing the Eu^(3+) ions concentration,which was also demonstrated by the X-ray diffraction(XRD),scanning electron microscopy(SEM),diffuse reflectance spectra(DRS),and photoluminescence excitation(PLE) analyses,Both the sintering temperature and the Eu^(3+)ions doping concentration have significant impact on the formation of the crystal *** these phosphors sintered at 1023 K exhibit two major luminescence lines at 594 and 614 nm under nearuV light of 395 nm excitation,corresponding to Eu^(3+)ions typical transitions of ^(5)D_(0)→^(7)F_(1) and ^(5)D_(0)→^(7)F_(2).The optimum concentration of Eu^(3+) ions is 9 mol% for C-LBTO:xEu^(3+) samples and the quenching interaction type is the nearest-neighbor ion *** thermal stability of the C-LBTO:0.09Eu^(3+)sample was investigated in detail and the device application further suggests that C-LBTO:0.09Eu^(3+) can be used as a red phosphor for near-UV excited w-LEDs in lighting.

关键词： Phosphor Tantalate LED device Rare earths

Anomalies of Precipitation over China on Days with Tropical Cyclone Activity over the Bay of Bengal: Role of Moisture Transport

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Journal of Meteorological Research 2024年第2期38卷 368-382页

作者： Na WEI ying LI Xiaoting fan Nanjing Joint Institute for Atmospheric Sciences Nanjing 210041 State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081 Department of Atmospheric and Oceanic Sciences and Institute of Atmospheric Sciences Fudan UniversityShanghai 200433

Tropical cyclones over the Bay of Bengal(BoBTC)affect the precipitation over China,with distinct seasonal and daily *** study quantitatively examines the daily standardized precipitation anomalies(SPAs)over China on the days with BoBTC activities(storm-days)and related circulations,based on rainfall measurements at surface meteorological stations and ECMWF reanalysis data on a 0.25°×0.25°resolution during *** positive SPA is found over the stations in the two adjacent regions around BoB(Southwest China in May/November and southern Tibetan Plateau in October)and three distant regions(Southeast China and the northeastern boundary of the Qinghai-Tibet Plateau in May,and central North China in October).The SPA distributions are remarkably consistent with the integrated water vapor transport(IVT)*** IVT is found associated with the interaction between southwesterly(southerly)of the BoBTC circulation and low-level monsoonal flow in May(midlevel westerly in winter months).The probabilities of extreme precipitation(EP)occurrences over the above regions all increase on *** adjacent regions,EP is significantly correlated with the northward IVT anomalies to the east of BoBTC circulation,which strengthen the water vapor input through the southern *** IVT anomalies are stronger in May,benefited by the deep monsoonal southwesterlies than those in *** distant regions,EP is more closely related to the IVT anomaly extending back from *** moisture from BoB concentrates along a local low-level convergence line over Southeast China,being further facilitated by coexistence of the BoBTC depression and midlevel westerly trough in *** results highlight the interactions between BoBTCs and local weather systems that influence the general precipitation anomalies and occurrence of EP over China,especially over distant regions.

关键词： tropical cyclone Bay of Bengal precipitation anomaly moisture transport

Grain boundary-induced drastic sensing performance enhancement of Fe2O3 gas sensors for acetone

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Rare Metals 2024年第9期43卷 4412-4424页

作者： Tian-Jun Hu Yi-fan Li Yu-Zhu Tian ying Wang Ya-ru Chen Jun-Ming Zhang Er-Gui Luo Jian-Feng Jia Key Laboratory of Magnetic Molecules & Magnetic Information Materials Ministry of Education School of Chemical and Material ScienceShanxi Normal University

Exploring the structure-activity relationship between the performance of gas sensors and the structure of semiconductor metal oxide （SMO） nanomaterials is crucial for understanding and designing gas-sensing materials and overcoming the application limitations of SMO-based gas *** of a single SMO microstructure provides a promising solution to address this scientific problem due to its controllable *** this study,we control the grain boundary （GB） density of Fe2O3nanomaterials using a simple solvothermal *** have similar chemical compositions and crystal phases,providing an ideal platform for studying the influence of the GB density on the gas-sensing ***-sensing tests showed that the Fe2O3-1 sensor with medium GB density and the Fe2O3-2 sensor with high GB density had higher sensitivity and selectivity than the Fe2O3-0 sensors with low GB density before reaching the optimal operating ***,when the GB density increased,the response to acetone decreased slightly,whereas the optimal operating temperature *** work highlights the unique performance of the GB density in enhancing the gas sensitivity of a single SMO.

关键词： Charge transfer Gas sensors Grain boundary (GB) density Oxygen adsorption Semiconductor metal oxide (SMO)

Dynamic changes and surveillance function of prion protein expression in gastric cancer drug resistance

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World Journal of Gastroenterology 2011年第35期17卷 3986-3993页

作者： Ji-Heng Wang Jing-Ping Du ying-Hai Zhang Xiao-Jun Zhao ru-ying fan Zhi-Hong Wang Zi-Tao Wu ying Han Department of Gastroenterology Beijing Army General Hospital Beijing 100700 China Department of General Surgery Jiamusi University Medical College Jiamusi 154004 Heilongjiang Province China

AIM:To explore the dynamic changes of prion protein (PrPc) in the process of gastric cancer drug resistance and the role of PrPc expression in the prognosis of gastric cancer patients receiving ***:A series of gastric cancer cell lines resistant to different concentrations of adriamycin was established,and the expression of PrPc,Bcl-2 and Bax was detected in these *** was determined using Annexin V *** blotting and immunohisto-chemistry were performed to detect the expression of PrPc in patients receiving chemotherapy and to explore the role of PrPc expression in predicting the chemosensitivity and the outcome of gastric cancer patients receiving ***-up was performed for 2 ***:PrPc expression was increased with the increase in drug ***-2,together with PrPc,increased the level of anti-apoptosis of cancer *** PrPc expression predicted the enhanced level of anti-apoptosis and resistance to anticancer *** expression could be used as a marker for predicting the efficacy of chemotherapy and the prognosis of gastric *** PrPc expression predicted both poor chemosensitivity and a low 2-year survival ***,low PrPc expression predicted favorable chemosensitivity and a relatively high 2-year survival ***:PrPc expression is associated with histological types and differentiation of gastric cancer cells;The PrPc expression level might be a valuable marker in predicting the efficacy of chemotherapy and the prognosis of gastric cancer patients receiving chemotherapy.

关键词： Prion protein Gastric cancer Drug resistance Chemotherapy Apoptosis

Stretchable and self-healing conductive fibers from hierarchical silver nanowires-assembled network

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Nano Research 2024年第2期17卷 763-770页

作者： ying-ying Wu Hong Chen fan Zhang Pan Guo Haili Qin Huai-Ping Cong Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction Engineering School of Chemistry and Chemical EngineeringHefei University of TechnologyHefei 230009China

Conductive fibers(CFs)with features of high conductivity,stretchability,self-healability,and electromechanical stability are key components of the increasingly popular wearable ***,since the lack of structural design of conductive network and interfacial interaction between soft polymer and conductive additives,it is still hard to enable CFs to meet above ***,we describe a facial drawing method from a hydrogel reservoir which is remolded into ultrathin and stretchable CFs with excellent multi-responsive *** hydrogel reservoir was fabricated in synergy of an ice-templating method and in situ polymerization using the assembled framework as a *** on the effective fabrication mechanism,the diameter of CFs could be well-tuned from 90 to 400μm by adjusting the dipping depth of the glass rod,accompanied with conductivity increased from 0.75 to 2.5 S/*** the hierarchical network structure was well maintained in the CFs,professional performances have been proved on the stretchability and electromechanical *** presence of massive hydrogen bonding and Ag–S bond enabled the CFs with excellent self-healability under the conditions of contact,electric field,and near infrared light,***,the CFs with high sensing property could be integrated into an advanced textile sensor through an effective healing-induced integration strategy,demonstrating its great potentials as superior two-dimensional(2D)electronic skins.

关键词： conductive fibers self-assembled silver nanowires Ag–S coordination self-healing flexible sensors

Resolution Enhancement of SOHO/MDI Magnetograms

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Research in Astronomy and Astrophysics 2024年第6期24卷 358-367页

作者： ying Qin Kai-fan Ji Hui Liu Xiao-Guang Yu Yunnan Observatories Chinese Academy of SciencesKunming 650011China University of Chinese Academy of Sciences Beijing 100049China Yunnan Key Laboratory of Solar Physics and Space Science Kunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China

Research on the solar magnetic field and its effects on solar dynamo mechanisms and space weather events has benefited from the continual improvements in instrument resolution and measurement *** augmentation and assimilation of historical observational data timelines also play a significant role in understanding the patterns of solar magnetic field *** the realm of astronomical data processing,super-resolution(SR)reconstruction refers to the process of using a substantial corpus of training data to learn the nonlinear mapping between low-resolution(LR)and high-resolution(HR)images,thereby achieving higherresolution astronomical *** paper is an application study in high-dimensional nonlinear *** learning models were employed to perform SR modeling on SOHO/MDI magnetograms and SDO/HMI magnetograms,thus reliably achieving resolution enhancement of full-disk SOHO/MDI magnetograms and enhancing the image resolution to obtain more detailed *** this study,a data set comprising 9717pairs of data from 2010 April to 2011 February was used as the training set,1332 pairs from 2011 March were used as the validation set and 1034 pairs from 2011 April were used as the test *** data preprocessing,we randomly cropped 128×128 sub-images as the LR cases from the full-disk MDI magnetograms,and the corresponding 512×512 sub-images as HR ones from the HMI full-disk magnetograms for model *** tests conducted have shown that the study successfully produced reliable 4×SR reconstruction of full-disk MDI *** MESR model's results(0.911)were highly correlated with the target HMI magnetographs as indicated by the correlation coefficient ***,the method achieved the best PSNR,SSIM,MAE and RMSE values,indicating that the MESR model can effectively reconstruct magnetograms.

关键词： magnetic fields techniques:image processing virtual observatory tools Sun:magnetic fields

Designing metal-organic framework fiber network reinforced polymer electrolytes to provide continuous ion transport in solid state lithium metal batteries

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Nano Research 2024年第4期17卷 2719-2727页

作者： Wanqing fan ying Huang Meng Yu Kaihang She Jingren Gou Zheng Zhang MOE Key Laboratory of Material Physics and Chemistry Under Extraordinary Conditions School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Beijing Key Laboratory of Membrane Materials and Engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

Polyethylene oxide(PEO)-based solid-state electrolytes are considered ideal for electrolyte materials in solid-state lithium metal batteries(SSLMBs).However,practical applications are hindered by the lower conductivity and poor interfacial ***,we propose a strategy to construct a three-dimensional(3D)fiber network of metal-organic frameworks(MOFs).Composite solid electrolytes(CSEs)with continuous ion transport pathways were fabricated by filling a PEO polymer matrix in fibers containing interconnected *** 3D fiber network provides a fast Li+transport path and effectively improves the ionic conductivity(1.36×10^(-4) S·cm^(-1),30℃).In addition,the network of interconnected MOFs not only effectively traps the anions,but also provides sufficient mechanical strength to prevent the growth of Li *** from the advantages of structural design,the CSEs stabilize the Li/electrolyte interface and extend the cycle life of the Li-symmetric cells to 3000 *** assembled SSLMBs exhibit excellent cycling performance at both room and high *** addition,the constructed pouch cells can provide an areal capacity of 0.62 mA·h·cm^(-2),which can still operate under extreme *** work provides a new strategy for the design of CSEs with continuous structure and stable operation of SSLMBs.

关键词： polyethylene oxide(PEO) solid-state lithium metal batteries(SSLMBs) three-dimensional fiber network composite solid electrolytes(CSEs)

Hollow Ni Mo-based nitride heterojunction with super-hydrophilic/aerophobic surface for efficient urea-assisted hydrogen production

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Journal of Energy Chemistry 2024年第8期95卷 428-439,I0009页

作者： Yuying fan ying Gu Dongxu Wang Yanqing Jiao Aiping Wu Chungui Tian Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People’s Republic of ChinaHeilongjiang UniversityHarbin 150080HeilongjiangChina College of Chemistry Chemical Engineering and Resource UtilizationNortheast Forestry UniversityHarbin 150040HeilongjiangChina

Hydrogen evolution reaction(HER)and urea oxidation reaction(UOR)are key reactions of the watercycling associated catalytic process/*** design of catalysts with a super-hydrophilic/aerophobic structure and optimized electron distribution holds great ***,we have designed a threedimensional(3D)hollow Ni/NiMoN hierarchical structure with arrayed-sheet surface based on a onepot hydrothermal route for efficient urea-assisted HER based on a simple hydrothermal *** Ni/NiMoN catalyst exhibits super-hydrophilic/aerophobic properties with a small droplet contact angle of 6.07°and an underwater bubble contact angle of 155.7°,thus facilitating an escape of bubbles from the *** functional theory calculations and X-ray photoelectron spectroscopy results indicate the optimized electronic structure at the interface of Ni and NiMoN,which can promote the adsorption/desorption of reactants and *** virtues combining with a large specific surface area endow Ni/NiMoN with efficient catalytic activity of low potentials of 25 mV for HER and 1.33 V for UOR at10 mA cm^(-2).The coupled HER and UOR system demonstrates a low cell voltage of 1.42 V at 10 mA cm^(-2),which is approximately 209 mV lower than water electrolysis.

关键词： Hydrogen evolution Transition metal nitrides Hollow heterojunctions Urea electrooxidation Super hydrophilic/aerophobic

Understanding Urban Vitality from the Economic and Human Activities Perspective:A Case Study of Chongqing,China

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Chinese Geographical Science 2024年第1期34卷 52-66页

作者： YANG Fiona fan LIN Geng LEI Yubing WANG ying YI Zheng School of Geography and Planning Sun Yat-sen UniversityGuangzhou510006China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai519100China Chongqing Planning and Design Institute Chongqing401147China

The literature on urban vitality tends to focus on the built *** paper argues that some important processes in shaping vitality may be overlooked without examining the intensity and diversity of economic and human *** newly developed spatial big data and adopting the methods of multi-indicator measurement and spatial analysis methods,we analyzed the pattern of urban vitality in Chongqing,a provincial city in western China and,on this basis,evaluated the creation and maintenance of urban vitality from the economic and human activities *** findings indicate that the impacts of economic and human activities are positive and *** the three intensity and diversity indicators,economic intensity and population density show an effect on urban vitality stronger than that of economic ***,economic diversity has the strongest superposition or interactive effect,and is thus an important foundation *** positive effect of population density on urban vitality is largely a result of Chongqing’s jobs-housing *** case of Chongqing highlights the importance of topographic features,historical inheritance,large-scale migration,and cultural activities in shaping the distinctive vitality pattern of a *** study contends that the creation and maintenance of urban vitality can not be fully explained without incorporating the impacts of economic and human *** contributes to a comprehensive measurement of urban vitality and enriches its connotations.

关键词： urban vitality economic diversity economic intensity population density Chongqing,China