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Transcriptional regulation in the development and dysfunction of neocortical projection neurons 被引量:1
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作者 Ningxin Wang Rong Wan Ke Tang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期246-254,共9页
Glutamatergic projection neurons generate sophisticated excitatory circuits to integrate and transmit information among different cortical areas,and between the neocortex and other regions of the brain and spinal cord... Glutamatergic projection neurons generate sophisticated excitatory circuits to integrate and transmit information among different cortical areas,and between the neocortex and other regions of the brain and spinal cord.Appropriate development of cortical projection neurons is regulated by certain essential events such as neural fate determination,proliferation,specification,differentiation,migration,survival,axonogenesis,and synaptogenesis.These processes are precisely regulated in a tempo-spatial manner by intrinsic factors,extrinsic signals,and neural activities.The generation of correct subtypes and precise connections of projection neurons is imperative not only to support the basic cortical functions(such as sensory information integration,motor coordination,and cognition)but also to prevent the onset and progression of neurodevelopmental disorders(such as intellectual disability,autism spectrum disorders,anxiety,and depression).This review mainly focuses on the recent progress of transcriptional regulations on the development and diversity of neocortical projection neurons and the clinical relevance of the failure of transcriptional modulations. 展开更多
关键词 autism spectrum disorders COGNITION differentiation excitatory circuits intellectual disability NEOCORTEX neurodevelopmental disorders projection neuron specification transcriptional regulation
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Compartmentalized regulation of organelle integrity in neurodegenerative diseases:lessons from the Drosophila motor neuron
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作者 Hyun Sung 《Neural Regeneration Research》 SCIE CAS 2025年第1期195-196,共2页
Neurons are highly polarized,morphologically asymmetric,and functionally compartmentalized cells that contain long axons extending from the cell body.For this reason,their maintenance relies on spatiotemporal regulati... Neurons are highly polarized,morphologically asymmetric,and functionally compartmentalized cells that contain long axons extending from the cell body.For this reason,their maintenance relies on spatiotemporal regulation of organelle distribution between the somatodendritic and axonal domains.Although some organelles,such as mitochondria and smooth endoplasmic reticulum,are widely distributed throughout the neuron,others are segregated to either the somatodendritic or axonal compartment.For example,Golgi outposts and acidified lysosomes are predominantly present in the somatodendritic domain and rarely distributed along the axon,whereas newly formed autophagosomes and synaptic vesicles are mainly distributed in the distal axon(Britt et al.,2016). 展开更多
关键词 ORGANELLE regulation DISTRIBUTION
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Eu(Ibu)_(3)phen配合物的合成表征及发光性
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作者 王莹 沈景辉 +3 位作者 胡丽娜 马冬云 史成阳 李炳寅 《吉首大学学报(自然科学版)》 CAS 2024年第3期88-90,共3页
以药物布洛芬为第一配体,稀土离子Eu(Ⅲ)为中心离子,采用溶剂法合成了Eu^(3+)、布洛芬(Ibu)和邻菲罗啉(phen)的稀土-布洛芬药物配合物Eu(Ibu)3phen,采用元素分析、紫外光谱、红外光谱对配合物进行了初步结构表征,并研究了配合物的荧光性... 以药物布洛芬为第一配体,稀土离子Eu(Ⅲ)为中心离子,采用溶剂法合成了Eu^(3+)、布洛芬(Ibu)和邻菲罗啉(phen)的稀土-布洛芬药物配合物Eu(Ibu)3phen,采用元素分析、紫外光谱、红外光谱对配合物进行了初步结构表征,并研究了配合物的荧光性能.结果表明,该合成方法简单,Eu(Ibu)_(3)phen产率较高,配合物Eu(Ibu)_(3)phen的荧光发射光谱在612 nm出现Eu离子强特征荧光发射峰.该配合物有较好的发光性能,可作为安全环保的荧光材料. 展开更多
关键词 稀土配合物 eu 布洛芬 荧光性质
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红色荧光粉CaAlSiN_(3)∶Eu^(2+)的结构精修和性能
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作者 林莹 刘梦丽 +3 位作者 冯嘉雯 郑文旭 胡晓琳 庄乃锋 《福州大学学报(自然科学版)》 CAS 北大核心 2024年第2期207-212,共6页
运用高温固相法合成系列掺铕(Eu)的氮化物荧光粉Ca1-xAlSiN_(3)∶xEu^(2+),对所得到的最佳样品Ca_(0.99)AlSiN_(3)∶0.01Eu^(2+)进行系列表征和结构精修.结果表明,样品Ca_(0.99)AlSiN_(3)∶0.01Eu^(2+)的晶粒尺寸为10μm左右,各元素分... 运用高温固相法合成系列掺铕(Eu)的氮化物荧光粉Ca1-xAlSiN_(3)∶xEu^(2+),对所得到的最佳样品Ca_(0.99)AlSiN_(3)∶0.01Eu^(2+)进行系列表征和结构精修.结果表明,样品Ca_(0.99)AlSiN_(3)∶0.01Eu^(2+)的晶粒尺寸为10μm左右,各元素分布均匀,其精修图与实测XRD谱图基本吻合,属于正交晶系结构.该样品的色坐标为(0.645 1, 0.354 5),落在红光区域,色纯度高达100%,相关色温为2 449 K,属于低色温.该荧光粉在298~473 K范围内表现出良好的热稳定性,活化能为0.26 eV,具有广阔的市场前景. 展开更多
关键词 红色荧光粉 铕掺杂 RIETVELD精修 发光性能 热稳定性
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Eu掺杂ZnO多孔片状材料的制备及其降解印刷染料RhB
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作者 吴娟 王晶 +3 位作者 王刚 李丹婷 李英豪 王健俐 《当代化工》 CAS 2024年第4期764-768,共5页
采用常温络合-水解法构筑Eu掺杂Zn O多孔片状材料。通过SEM、TEM、XRD、EDS等表征手段证明稀土元素Eu成功掺杂到Zn O之中,Eu-Zn O的形貌为多孔片状结构。研究了Eu-Zn O多孔片状材料对染料的光催化性能。结果表明:该材料对Rh B具有较好... 采用常温络合-水解法构筑Eu掺杂Zn O多孔片状材料。通过SEM、TEM、XRD、EDS等表征手段证明稀土元素Eu成功掺杂到Zn O之中,Eu-Zn O的形貌为多孔片状结构。研究了Eu-Zn O多孔片状材料对染料的光催化性能。结果表明:该材料对Rh B具有较好的降解效率,降解效率高达99.2%,循环稳定性能高达98.3%,远大于商用Zn O的76.2%的降解效率和82.3%的循环稳定性能,由以上数据说明Eu-Zn O具有很好的光催化降解效率和循环稳定性能。其优异的光催化性能归因于稀土元素Eu掺杂和多孔片状结构。 展开更多
关键词 eu-Zn O Rh B 常温络合-水解法 光催化
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高压水蒸气对β-Li_(2)TiO_(3:)Eu^(3+)荧光粉的全谱发光性能影响
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作者 于成龙 刘冠华 +6 位作者 刘子航 金党波 程航 齐勇 王志齐 李海 王秀峰 《陕西科技大学学报》 北大核心 2024年第2期138-145,共8页
采用水热法制备荧光粉前驱体后通过高温煅烧的方法,合成了由电偶极跃迁主导的高色纯度的β-Li_(2)TiO_(3):Eu^(3+)红色荧光粉.设计了适用于DHT11的拓扑电路,对荧光粉体湿度和温度进行测试.研究发现,高压腔体中加水量为5 mL,β-Li_(2)TiO... 采用水热法制备荧光粉前驱体后通过高温煅烧的方法,合成了由电偶极跃迁主导的高色纯度的β-Li_(2)TiO_(3):Eu^(3+)红色荧光粉.设计了适用于DHT11的拓扑电路,对荧光粉体湿度和温度进行测试.研究发现,高压腔体中加水量为5 mL,β-Li_(2)TiO_(3):0.5 mol%Eu^(3+)的相对湿度可达81%RH.在波长为396 nm的近紫外光激发下,β-Li_(2)TiO_(3):0.5 mol%Eu^(3+)发射由电偶极跃迁主导的613 nm的红光,荧光寿命为773.36μs,高压水蒸气处理对β-Li_(2)TiO_(3):0.5 mol%Eu^(3+)的电偶极跃迁发射峰和磁偶极跃迁发射峰位置没有变化,但发射峰强度增强并且荧光寿命降至386.81μs.高压水蒸气高压处理后的荧光粉色坐标x=0.47,y=0.51,色温为3300 K,红光色纯度为96.6%,比高压处理前显示出更优异的显色性能.高压水蒸气处理后的β-Li_(2)TiO_(3):0.5 mol%Eu^(3+)电偶极跃迁谱线强度参数Ω_(2)增加至4.21×10^(-19)cm^(2),^(5)D_(0)→^(7)F_(2)跃迁的荧光分支比β2也增加至96.9%,而量子效率η减小至57%,证实了湿度对荧光粉的发光效率具有极大的影响. 展开更多
关键词 高压水蒸气 β-Li_(2)TiO_(3:)eu^(3+)荧光粉 湿度
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Mannose metabolism and immune regulation:Insights into its therapeutic potential in immunology-related diseases
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作者 QINGPAN BU PING LI +2 位作者 YUNFEI XIA XINPEI WEI KAI SONG 《BIOCELL》 SCIE 2023年第11期2535-2546,共12页
Mannose,a different isomer of the hydroxyl group at the C-2 position of glucose,shares the same transport carrier protein with glucose to enter cells and participate in the regulation of glucose metabolism.It affects ... Mannose,a different isomer of the hydroxyl group at the C-2 position of glucose,shares the same transport carrier protein with glucose to enter cells and participate in the regulation of glucose metabolism.It affects cell growth,differentiation,and function and plays an active role in tumor immunity and inflammatory processes.This paper provides theoretical support for expanding the clinical applications of mannose by exploring its constitution,metabolic pathways,and role in regulating immune cell function and treating immunology-related diseases. 展开更多
关键词 MANNOSE METABOLISM Immune cell Immune regulation
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用于痕量监测Zr^(4+)、Cr_(2)O_(7)^(2-)、Fe^(3+)、HPO_(4)^(2-)和指纹识别的功能化Eu^(3+)/Tb^(3+)配位聚合物荧光探针的构筑
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作者 王思璐 张凤凤 +5 位作者 张成 王潇 唐龙 岳二林 王记江 侯向阳 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第2期441-450,共10页
采用芳香族π共轭及含氮原子有机连接剂,合成同构铽、铕发光配位聚合物(CPs){[Eu(PLIA)_(1.5)(H_(2)O)_(2)]·H_(2)O}_(n)(1)和{[Tb(PLIA)_(1.5)(H_(2)O)_(2)]·H_(2)O}_(n)(2),其中H_(2)PLIA=5-((吡啶-4-基甲基)氧基)苯-1,3-... 采用芳香族π共轭及含氮原子有机连接剂,合成同构铽、铕发光配位聚合物(CPs){[Eu(PLIA)_(1.5)(H_(2)O)_(2)]·H_(2)O}_(n)(1)和{[Tb(PLIA)_(1.5)(H_(2)O)_(2)]·H_(2)O}_(n)(2),其中H_(2)PLIA=5-((吡啶-4-基甲基)氧基)苯-1,3-二甲酸。对合成的配合物进行了结构测定、表征和荧光痕量识别实验研究。2个同构配合物具有理想的三维框架结构,π…π堆积及氢键等弱相互作用增强了其化学稳定性;表征显示配位聚合物1和2具有良好的荧光性质、结晶性、热力学稳定性及结构完整性,可作为荧光传感的材料。1和2对水溶液中的Zr^(4+)、Cr_(2)O_(7)^(2-)和Fe^(3+)、HPO_(4)^(2-)具有选择性好、灵敏度高的荧光识别能力,其检出限分别为0.139μmol·L^(-1)(1,Zr^(4+))、0.626μmol·L^(-1)(1,Cr_(2)O_(7)^(2-))、0.430μmol·L^(-1)(2,Fe^(3+))、1.36μmol·L^(-1)(2,HPO_(4)^(2-))。探究了1和2作为探针的荧光猝灭机理。更有趣的是,1和2具有指纹识别性能,其荧光指纹纹路清晰连贯,细节明显,可被清晰观察。 展开更多
关键词 eu^(3+)/Tb^(3+)配位聚合物 合成 表征 荧光探针 指纹识别
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生态设计法规(EU)2023/826应用分析
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作者 胡乐宏 刘婷 《电子质量》 2024年第3期105-108,共4页
2023年4月18日,欧盟委员会正式发布了基于生态设计指令2009/125/EC框架下电气产品关机、待机等模式下生态设计要求新法规(EU)2023/826,该法规自2023年5月9日起生效,强制执行日期为2025年5月9日。同时,同步废除原家用和办公电子电气设备... 2023年4月18日,欧盟委员会正式发布了基于生态设计指令2009/125/EC框架下电气产品关机、待机等模式下生态设计要求新法规(EU)2023/826,该法规自2023年5月9日起生效,强制执行日期为2025年5月9日。同时,同步废除原家用和办公电子电气设备待机和关机模式、网络待机模式生态设计法规(EU)1275/2008,以及简易机顶盒生态设计法规(EU)107/2009。主要变化点有取消对低压外部电源供电产品的豁免和信息技术设备的关机、待机状态下的功耗变化。结合(EC)1275/2008和(EU)2023/826相关要求,主要分析了法规的差异,为信息技术设备功耗设计提供了借鉴。 展开更多
关键词 (eu)1275/2008 (eu)2023/826 生态设计法规
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一例Eu-MOF材料的构筑及对Fe^(3+)与硝基芳香族爆炸物的荧光检测性能
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作者 冀超 李文 +2 位作者 张丽荣 华佳 刘云凌 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2024年第2期16-24,共9页
金属阳离子和硝基芳香族爆炸物的大量排放对环境和人体健康造成了严重威胁,对它们的高效检测具有重要的研究意义和挑战性,金属-有机骨架(MOFs)是一类新型的荧光传感检测材料.本文采用溶剂热法合成了一例具有fcu拓扑结构的Eu-MOF材料,[(C... 金属阳离子和硝基芳香族爆炸物的大量排放对环境和人体健康造成了严重威胁,对它们的高效检测具有重要的研究意义和挑战性,金属-有机骨架(MOFs)是一类新型的荧光传感检测材料.本文采用溶剂热法合成了一例具有fcu拓扑结构的Eu-MOF材料,[(CH_(3))_(2)NH_(2)]_(2)[Eu_(6)(μ_(3)-OH)_(8)(EDDC)_(6)]·8DMA·3MeOH·6H_(2)O[JLUMOF128,H_(2)EDDC=(E)-4,4′-(乙烯-1,2-取代基)二苯甲酸],并通过单晶X射线衍射、粉末X射线衍射、X射线光电子能谱、红外光谱、元素分析和热重分析对其结构及组成进行了表征.结果表明,由于荧光配体H_(2)EDDC的引入,JLU-MOF128表现出显著的荧光性能,在DMF溶液中对Fe^(3+)、2,4,6-三硝基苯酚(TNP)和2,4-二硝基苯酚(2,4-DNP)具有较好的检测效果,Ksv值分别为2.09×10^(4),8.49×10^(4)和5.75×10^(4)L/mol,检测限分别为5.99,1.51和1.93μmol/L.在金属阳离子和硝基芳香族爆炸物的检测方面,JLU-MOF128是一种理想的多感应荧光传感材料. 展开更多
关键词 铕-金属-有机骨架 荧光检测 Fe^(3+)离子 硝基芳香族爆炸物
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Effect of Different Soil Regulation Measures on Yield and Soil Fertility of Eucalyptus Plantation in Southern Guangxi
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作者 Fei GUO Caili HUANG +2 位作者 Xiajie QIN Weijian LIAO Jiang TANG 《Meteorological and Environmental Research》 CAS 2023年第1期29-34,40,共7页
In view of the problems of decreased unit yield,soil acidification,decreased soil organic matter and soil fertility caused by high generation single pure Eucalyptus plantation in southern Guangxi,a field experiment wa... In view of the problems of decreased unit yield,soil acidification,decreased soil organic matter and soil fertility caused by high generation single pure Eucalyptus plantation in southern Guangxi,a field experiment was conducted to study the yield,soil organic matter and soil fertility under six soil conditioning measures[interplanting Tephrosia candida under the forest,interplanting Sesbania cannabina under the forest,organic fertilizer application,residue to woodland,soil testing and formulated fertilization,and applying pure chemical fertilizer(CK)],and the enhancing effects of each treatment on the yield and soil improvement of Eucalyptus plantations were further comprehensively evaluated.The results showed that compared with the control,the five treatments could increase the average stock of Eucalyptus,among which the average stock under the treatment of interplanting T.candida under the forest was the highest,followed by soil testing and formulated fertilization.The soil organic matter content and soil fertility of the forest were significantly improved by interplanting green manure,organic fertilizer application and soil testing and formulated fertilization models,while the short-term(1 a)effect of the residue treatment on the improvement of soil organic matter and soil fertility was insignificant.During the actual production process,interplanting green manure and residue treatment were not effective due to the inoperability,and the applicability were not wide,which still needed further study.Therefore,organic manure application and soil testing and formulated fertilization were suitable choices to promote the improvement of productivity and soil quality of Eucalyptus plantation in Guangxi. 展开更多
关键词 eucalyptus plantation Soil regulation measures Stand volume Soil fertility
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Sr_(2)InP_(3)O_(11):Eu^(3+)红色荧光粉的发光性能及占位影响
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作者 梁力 赵淑娟 +3 位作者 李贵花 刘一佳 王荣荣 蔡格梅 《发光学报》 EI CAS CSCD 北大核心 2024年第6期913-922,共10页
红色荧光粉是提高发光二极管(LED)显色指数、降低色温的重要组分。本文选择具有红色特征发射的Eu^(3+)作为激活剂离子,以新型磷酸盐Sr_(2)InP_(3)O_(11)为荧光粉基质,通过高温固相反应合成了系列Sr_(2-x)InP_(3)O_(11):xEu^(3+)(简化为S... 红色荧光粉是提高发光二极管(LED)显色指数、降低色温的重要组分。本文选择具有红色特征发射的Eu^(3+)作为激活剂离子,以新型磷酸盐Sr_(2)InP_(3)O_(11)为荧光粉基质,通过高温固相反应合成了系列Sr_(2-x)InP_(3)O_(11):xEu^(3+)(简化为S_(2-x)IP_(3):xEu^(3+))和Sr_(2)In_(1-x)P_(3)O_(11):xEu^(3+)(简化为S_(2)I_(1-x)P_(3):xEu^(3+))荧光粉。利用XRD、室温及变温PL光谱、量子效率和荧光寿命,详细研究了所制备荧光粉的光致发光性能及其受阳离子位点(Sr位和In位)的影响规律。研究结果表明,这两类荧光粉在254nm和393nm激发下均可发出明亮的橘红光(593nm和612nm主导)。此外,所合成的荧光粉具有较好的色稳定性和热稳定性,表明其在荧光粉转换型白光LED照明和显示领域具有一定的发展潜力。 展开更多
关键词 荧光粉 eu^(3+)掺杂 占位 发光性能
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高光产额SrI_(2)Eu^(2+)晶体制备及其闪烁性能研究
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作者 金鹏 张春生 +9 位作者 欧阳晓平 刘金良 陈亮 何世熠 阮金陆 孙涛峰 王方宝 刘林月 张显鹏 张建福 《现代应用物理》 2024年第1期28-33,共6页
SrI_(2)Eu^(2+)晶体因其极高的光产额和优良的能量分辨率,在伽马射线高分辨测量中呈现出良好的应用前景。采用改进的坩埚下降法制备出掺杂浓度为5.0%的SrI_(2)Eu^(2+)晶体,加工制成了直径为25 mm,厚度分别为3,6,9,12 mm的单透光防潮封装... SrI_(2)Eu^(2+)晶体因其极高的光产额和优良的能量分辨率,在伽马射线高分辨测量中呈现出良好的应用前景。采用改进的坩埚下降法制备出掺杂浓度为5.0%的SrI_(2)Eu^(2+)晶体,加工制成了直径为25 mm,厚度分别为3,6,9,12 mm的单透光防潮封装SrI_(2)Eu^(2+)闪烁体。研究了4种不同尺寸闪烁体对^(241)Am,^(137)Cs,^(60)Co放射源伽马射线的响应,测试了SrI_(2):Eu^(2+)晶体的荧光光谱、能量分辨率、发光产额及衰减时间等闪烁性能。实验结果表明:SrI_(2)Eu^(2+)晶体的发光光谱峰值位于436 nm,SrI_(2)Eu^(2+)晶体闪烁性能随晶体厚度减薄或伽马射线能量的提高而提升。3 mm厚度SrI_(2)Eu^(2+)闪烁体对1.173 MeV^(60)Co伽马射线的能量分辨率达到了2.74%,在^(137)Cs源伽马射线激发下,光产额达到1.23×10^(5)MeV^(-1),是传统NaI:Tl闪烁体光产额的3倍以上,与当前国际上报道的最好的实验结果相当。 展开更多
关键词 SrI_(2)eu^(2+)晶体 坩埚下降法 脉冲幅度谱 发光产额 能量分辨率
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NaCa_(2)Mg_(2)(VO_(4))_(3)∶Eu^(3+)颜色可调荧光粉的熔盐法合成及其发光性能研究
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作者 陈金润 陈梦玉 +4 位作者 李子璇 李微 楚楚 曹秀哲 翟永清 《人工晶体学报》 北大核心 2024年第1期90-96,共7页
以廉价的NaCl为熔盐,采用熔盐法合成了NaCa_(2-x)Mg_(2)(VO_(4))_(3)∶xEu^(3+)(0≤x≤0.10)系列颜色可调荧光粉,系统研究了合成条件、Eu^(3+)掺杂对样品结构及发光性能的影响。结果表明,反应温度为800℃、反应时间为0.5 h、原料与熔盐... 以廉价的NaCl为熔盐,采用熔盐法合成了NaCa_(2-x)Mg_(2)(VO_(4))_(3)∶xEu^(3+)(0≤x≤0.10)系列颜色可调荧光粉,系统研究了合成条件、Eu^(3+)掺杂对样品结构及发光性能的影响。结果表明,反应温度为800℃、反应时间为0.5 h、原料与熔盐的质量比为1∶3是合成NaCa_(2)Mg_(2)(VO4)_(3)的适宜反应条件,所得样品为NaCa_(2)Mg_(2)(VO_(4))_(3)纯相,且结晶度高。样品微观形貌随着反应温度的升高由珊瑚状演变为表面光滑的不规则多面体。Eu^(3+)掺杂对NaCa_(2)Mg_(2)(VO_(4))_(3)的晶体结构影响较小,但对其发光性能影响较大。随着Eu^(3+)浓度(x)的增加,VO_(4)^(3-)的特征发射带强度逐渐减弱;而Eu^(3+)的特征发射峰强度先增大后减小,当x=0.06时,达到最大。故通过改变Eu^(3+)浓度,可对样品的发光颜色进行调制,从绿色可调制为黄绿色、黄色、黄白色、橙红色。荧光光谱与荧光寿命分析表明,NaCa_(2)Mg_(2)(VO_(4))_(3)∶Eu^(3+)体系中存在VO43-到Eu^(3+)的能量转移过程,能量转移效率约为23%;热稳定性分析结果表明,当温度从室温(298.15 K)升高到398.15 K时,NaCa_(1.94)Mg_(2)(VO_(4))_(3)∶0.06Eu^(3+)荧光粉在614 nm处的主发射峰强度可保留起始值的68.4%,表现出良好的热稳定性。 展开更多
关键词 钒酸盐 熔盐法 发光性能 白光LED 颜色可调荧光粉 铕离子掺杂
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高效率BaAl_(4)Sb_(2)O_(12)∶Eu^(2+)荧光粉合成与发光性能
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作者 王凯旋 周雪莲 +5 位作者 张钰 王泽 苏日力格 哈拉木吉 田启旭 朝克夫 《发光学报》 EI CAS CSCD 北大核心 2024年第5期753-761,共9页
白光LED作为第四代照明光源已经广泛应用到人们生活的各个领域,其中荧光粉是获得高性能白光LED的关键材料之一。如何用简单的方法制备高性能的荧光粉是目前研究人员的一个挑战性工作。本文采用高温固相法,加入助熔剂H_(3)BO_(3)、NH_(4... 白光LED作为第四代照明光源已经广泛应用到人们生活的各个领域,其中荧光粉是获得高性能白光LED的关键材料之一。如何用简单的方法制备高性能的荧光粉是目前研究人员的一个挑战性工作。本文采用高温固相法,加入助熔剂H_(3)BO_(3)、NH_(4)Cl、SrF_(2)、LiF和BaF_(2),成功制备了BaAl_(4)Sb_(2)O_(12)∶Eu^(2+)(BASO∶Eu^(2+))荧光粉。通过晶体结构分析、发射光谱、X射线光电子能谱(XPS)以及荧光寿命分析,表明过量的Sb_(2)O_(3)能够有效地将Eu^(3+)还原成Eu^(2+),提高Eu^(2+)在563 nm处的荧光强度约12.5倍,内量子效率(IQE)可以达到96.14%。另外,还研究了不同助熔剂对荧光粉晶体结构、荧光强度以及内量子效率的影响。本实验采用的方法简单,避免使用具有一定危险的还原性气体烧结,易于工业化应用以及降低生产成本。 展开更多
关键词 BaAl_(4)Sb_(2)O_(12)∶eu^(2+) 还原作用 助熔剂 白光LEDs
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OsPPG encodes a pseudouridine-5'-phosphate glycosidase and regulates rice spikelet development
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作者 Rui Chen Dagang Tian +9 位作者 Yarong Lin Jiaqing Huang Qinqin Yang Yupei Li Huaqing Liu Shaohua Yang Jingyang Chen Shufen Zhou Feng Wang Shubiao Zhang 《The Crop Journal》 SCIE CSCD 2024年第3期698-708,共11页
Florets are the basic structural units of spikelets,and their morphogenesis determines the yield and quality of rice grains.However,whether and how pseudouridine-5’-phosphate glycosidase participates in rice spikelet... Florets are the basic structural units of spikelets,and their morphogenesis determines the yield and quality of rice grains.However,whether and how pseudouridine-5’-phosphate glycosidase participates in rice spikelet development remains an open question.In this study,we identified a novel gene,OsPPG,which encodes a peroxisome-localized pseudouridine-5’-phosphate glycosidase and regulates the development of rice spikelets.osppg mutants exhibited abnormal sterile lemma,lemma,palea,lodicule,stamens,and pistils;male sterility;shorter panicles;and reduced plant height.OsPPG was found to regulate several OsMADS genes,thereby affecting the morphogenesis of rice spikelets.Furthermore,metabolomics revealed that the OsPPG gene was involved in the decomposition of pseudouridine via the pyrimidine metabolism pathway and may affect the jasmonic acid signaling pathway.These results suggest that OsPPG is a key regulator of rice spikelet development. 展开更多
关键词 OsPPG Reproductive regulation Spikelet development RICE
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Dynamic regulation of the irrigation-nitrogen-biochar nexus for the synergy of yield,quality,carbon emission and resource use efficiency in tomato
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作者 Ping’an Zhang Mo Li +5 位作者 Qiang Fu Vijay PSingh Changzheng Du Dong Liu Tianxiao Li Aizheng Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期680-697,共18页
Integrated water and fertilizer management is important for promoting sustainable development of facility agriculture,and biochar plays an important role in guaranteeing food production,as well as alleviating water sh... Integrated water and fertilizer management is important for promoting sustainable development of facility agriculture,and biochar plays an important role in guaranteeing food production,as well as alleviating water shortages and the overuse of fertilizers.The field experiment had twelve treatments and a control(CK)trial including two irrigation amounts(I1,100%ETm;I2,60%ETm;where ETm is the maximum evapotranspiration),two nitrogen applications(N1,360 kg ha^(−1);N2,120 kg ha^(−1))and three biochar application levels(B1,60 t ha^(−1);B_(2),30 t ha^(−1)and B3,0 t ha^(−1)).A multi-objective synergistic irrigation-nitrogen-biochar application system for improving tomato yield,quality,water and nitrogen use efficiency,and greenhouse emissions was developed by integrating the techniques of experimentation and optimization.First,a coupled irrigation-nitrogen-biochar plot experiment was arranged.Then,tomato yield and fruit quality parameters were determined experimentally to establish the response relationships between irrigation-nitrogen-biochar dosage and yield,comprehensive quality of tomatoes(TCQ),irrigation water use efficiency(IWUE),partial factor productivity of nitrogen(PFPN),and net greenhouse gas emissions(NGE).Finally,a multi-objective dynamic optimization regulation model of irrigation-nitrogen-biochar resource allocation at different growth stages of tomato was constructed which was solved by the fuzzy programming method.The results showed that the application of irrigation and nitrogen to biochar promoted increase in yield,IWUE and PFPN,while it had an inhibitory effect on NGE.In addition,the optimal allocation amounts of water and fertilizer were different under different scenarios.The yield of the S1 scenario increased by 8.31%compared to the B_(1)I_(1)N_(2) treatment;TCQ of the S2 scenario increased by 5.14%compared to the B_(2)I_(2)N_(1) treatment;IWUE of the S3 scenario increased by 10.01%compared to the B1I2N2 treatment;PFPN of the S4 scenario increased by 9.35%compared to the B_(1)I_(1)N_(2) treatment;and NGE of the S5 scenario decreased by 11.23%compared to the B_(2)I1N1 treatment.The optimization model showed that the coordination of multiple objectives considering yield,TCQ,IWUE,PFPN,and NGE increased on average from 4.44 to 69.02%compared to each treatment when the irrigation-nitrogen-biochar dosage was 205.18 mm,186 kg ha^(−1)and 43.31 t ha^(−1),respectively.This study provides a guiding basis for the sustainable management of water and fertilizer in greenhouse tomato production under drip irrigation fertilization conditions. 展开更多
关键词 irrigation-nitrogen-biochar dynamic regulation multi-dimensional target collaboration TOMATO sustainability
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A short overview of the lead iodide residue impact and regulation strategies in perovskite solar cells
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作者 Eng Liang Lim Zhanhua Wei 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期504-510,I0012,共8页
Lead iodide(PbI2) is a vital raw material for preparing perovskite solar cells(PSCs),and it not only takes part in forming the light absorption layer but also remains in the grain boundary as a passivator.In other wor... Lead iodide(PbI2) is a vital raw material for preparing perovskite solar cells(PSCs),and it not only takes part in forming the light absorption layer but also remains in the grain boundary as a passivator.In other words,the PbI2 content in the precursor and as formed film will affect the efficiency and stability of the PSCs.With moderate residual PbI2,it passivates the bulk/surface defects of perovskite,reduces the interfacial recombination,promotes the perovskite stability,minimizes the device hysteresis,and so on.Deficient PbI2 residue will reduce the interfacial passivation effect and device performance.In addition to facilitating the non-radiative recombination,over PbI2 residue can also lead to electronic insulation in the grain boundary and deteriorate the device performance.However,the impact and regulation of PbI2 residue on the device performance and stability is still not fully understood.Herein,a comprehensive and detailed review is presented by discussing the PbI2 residue impact and its regulation strategies(i.e., elimination,facilitation and conversion of the residue PbI2) to manipulate the PbI2 content,distribution and forms.Finally,we also show future outlooks in this field,with an aim to help further the progression of high-efficiency and stable PSCs. 展开更多
关键词 Lead iodide RESIDUE regulation Perovskite solar cells Efficiency Stability
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关于欧盟电池新规(EU)2023/1542中电池碳足迹的介绍
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作者 刘伟 《中国标准化》 2024年第10期138-141,共4页
2023年7月28日,欧盟正式颁布了新电池法规——《2023年7月12日欧洲议会和理事会第2023/1542号法规(欧盟)关于电池和废旧电池,修订指令2008/98/EC和欧盟法规2019/1020以及废止指令2006/66/EC》,其中明确了对电池碳足迹的规定,这一新的规... 2023年7月28日,欧盟正式颁布了新电池法规——《2023年7月12日欧洲议会和理事会第2023/1542号法规(欧盟)关于电池和废旧电池,修订指令2008/98/EC和欧盟法规2019/1020以及废止指令2006/66/EC》,其中明确了对电池碳足迹的规定,这一新的规定将成为我国电池产品进入欧盟市场的新技术壁垒。本文对该法规中的碳足迹规定做了较为详细的介绍,包括范围、定义、功能单元和基准流、系统边界、公司特定和二次数据集的使用、碳足迹影响评价、偏移、碳足迹性能类别和最大碳阈值等,为国内电池设计和制造企业了解欧盟新电池法规中的碳足迹规定提供参考。 展开更多
关键词 欧盟法规 电池 碳足迹 生命周期
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A new liquid membrane diffusion model for characterizing the adsorption kinetics of europium by using a continuous measurement of adsorption platform
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作者 Hao-Qi Yu Tao Yu Jian-Hua Ye 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期59-72,共14页
To explore the kinetic adsorption under continuous and nonequilibrium states, an integration of continuous measurement and adsorption platform kinetics method was proposed, which was initially called the ICM-AP kineti... To explore the kinetic adsorption under continuous and nonequilibrium states, an integration of continuous measurement and adsorption platform kinetics method was proposed, which was initially called the ICM-AP kinetics method, and a corresponding kinetic adsorption experimental method was developed. Adsorption experiments of europium(Eu) on Ca-bentonite,Na-bentonite, and the D231 cation exchange resin were performed using the ICM-AP kinetics method and continuous measurements. Because the kinetic experimental results observed in this study were different from those of traditional batch adsorption data, pseudo-first-order or pseudo-second-order kinetic models were unsuitable for fitting the experimental data.Hence, a liquid membrane diffusion(LMD) model was developed based on the assumption of simultaneous adsorption/desorption to discuss the mechanism of kinetic adsorption. The kinetic adsorption mechanism was also studied by using XPS.The results indicated that the proposed adsorption model can fit the experimental data more suitably, and the adsorption/desorption behaviors of Eu on bentonite and the D231 resin were simultaneously observed, suggesting that the adsorption kinetics of Eu(Ⅲ) was mainly dominated by hydrated Eu(Ⅲ) ions on the liquid membrane. 展开更多
关键词 ICM-AP method LMD model Adsorption mechanism eu(Ⅲ)
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