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Reactions of Rare-Earth Metal Based Lewis Pairs with Azides

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Chinese Journal of Chemistry 2020年第6期38卷 559-564页

作者： yifan Dong Kejian Chang Xin Xu Key Laboratory of Organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhouJiangsu 215123China

The reactivity of homoleptic rare-earth metal aryloxide based Lewis pairs toward organic azide substrates has been investigated *** of RE(OAr)3(RE=La,Sm,X and Sc,Ar=2,6-'Bu2-C6H3),PEt3 and Me3siN3 in 2:1:1 molar ratio resulted in formation of separated ion pair complexes[Me3si-PEt3]^+[(ArO)3RE-N=N=N-RE(OAr)3]^-under mild *** of phosphine with the nitrogen-containing Lewis base l,4-diazabicyclo[2.2.2]octane(DABCO)produced analogous rare-earth azide complexes with[Me3si-DABCO]+*** contrast,reaction of the La(OAr)3/PEt3 Lewis pair with 1-adamantyl azide(AdN3)afforded the typical frustrated Lewis pair-type 1,1-addition product.A tetrahydrofuran ring-opening reaction was also observed for the resulting rare-earth azide complex with the[Me3si-PEt3]+cation,with cleavage of the C—0 bond by si/P cooperation.

关键词： azide rare complexes

格尔木河上游水成沉积物元素时空变化、流域风化及其驱动机制

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盐湖研究 2024年第1期32卷 10-19页

作者：程夏丽安福元李善禄司璐徐一帆张清纯柴璐琦青海师范大学青藏高原地表过程与生态保育教育部重点实验室青海西宁810008 青海师范大学地理科学学院青海省自然地理与环境过程重点实验室青海西宁810008 青海省人民政府-北京师范大学高原科学与可持续发展研究院青海西宁810008 中国建筑材料工业地质勘查中心青海总队青海岩土工程勘察院有限公司青海西宁810008

格尔木河流域上游山区沉积物元素的风化迁移规律对察尔汗盐湖中盐类资源的补给具有重要意义。文章结合已有的光释光(OSL)年代学数据,对该流域的上游纳赤台(NCT)和中游小干沟(XGG)剖面进行了主要常微量元素变化规律研究,并对流域内上下... 详细信息

格尔木河流域上游山区沉积物元素的风化迁移规律对察尔汗盐湖中盐类资源的补给具有重要意义。文章结合已有的光释光(OSL)年代学数据,对该流域的上游纳赤台(NCT)和中游小干沟(XGG)剖面进行了主要常微量元素变化规律研究,并对流域内上下游不同类型沉积物的元素特征进行对比分析,得出如下结论:1.末次间冰期以来,格尔木河中游河谷沉积物中主要元素含量较上游西大滩、昆仑河小流域次级盆地中高,表现出较为明显的富集状态。2.流域上游湿冷山前地带河谷沉积物的风化程度明显高于中游干热河谷,表明上游冰川融水和较充沛的降水条件导致充分的水岩反应过程是主导流域风化的主要因素,且物质在流域各个次级盆地间物质输送具有跳跃性、传递性和继承性。3.流域内的风化过程与晚更新世以来的冰期-间冰期气候旋回和季风-西风相互转换密切相关,即暖湿阶段主要受季风控制,以化学风化为主;干冷阶段受西风控制,以物理风化为主。综上,格尔木河流域上游山前地带元素的风化迁移和中游河谷沉积物对元素的继承转移是流域内物质流动的主要形式。

关键词：格尔木河流域元素迁移化学风化季风西风转换

针尖-样品距离对扫描微波显微成像的影响分析

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电子显微学报 2024年第3期43卷 303-308页

作者：薛一凡王采慧裴涛温焕飞中北大学仪器与电子学院仪器科学与动态测试教育部重点实验室山西太原030051

随着芯片制备工艺的不断完善,半导体集成电路朝着小型化、集成化的方向不断发展,给近场微波成像技术带来了新的挑战。本文建立了探针-样品三维电磁耦合模型,并利用有限元数值分析法研究了探针针尖与样品之间的电磁相互作用。在不同探针... 详细信息

随着芯片制备工艺的不断完善,半导体集成电路朝着小型化、集成化的方向不断发展,给近场微波成像技术带来了新的挑战。本文建立了探针-样品三维电磁耦合模型,并利用有限元数值分析法研究了探针针尖与样品之间的电磁相互作用。在不同探针-样品间距下,对硅基芯片表面结构进行扫描微波成像。成像结果与仿真结果相一致,随着针尖-样品间距的增加,扫描微波测试系统的灵敏度和分辨率降低。对于由原子力显微术结合微波测量技术发展而来的扫描微波显微镜的改进与产业化具有重大意义。

关键词：扫描微波显微镜有限元法电磁建模针尖-样品间距

Effect of charge trapping on electrical characteristics of silicon junctionless nanowire transistor

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Journal of Semiconductors 2022年第5期43卷 104-108页

作者： yifan Fu Liuhong Ma Zhiyong Duan Weihua Han School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China Engineering Research Center for Semiconductor Integrated Technology Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100083China Institute of Intelligence Sensing in Zhengzhou University Zhengzhou 450001China

We investigated the effect of charge trapping on electrical characteristics of silicon junctionless nanowire transistors which are fabricated on heavily n-type doped silicon-on-insulator substrate. The obvious random telegraph noise and current hysteresis observed at the temperature of 10 K indicate the existence of acceptor-like traps. The position depth of the traps in the oxide from si/siO_(2) interface is 0.35 nm, calculated by utilizing the dependence of the capture and emission time on the gate voltage. Moreover, by constructing a three-dimensional model of tri-gate device structure in COMSOL Multiphysics simulation software, we achieved the trap density of 1.9 × 10^(12) cm^(–2) and the energy level position of traps at 0.18 eV below the intrinsic Fermi level.

关键词： junctionless transistor charge trapping random telegraph signals

广州地区居住建筑遮阳对节能率的影响及其优化设计研究

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城市建筑 2021年第28期18卷 172-177页

作者：毛以沫司一凡赵立华广州城市理工学院建筑学院广东广州510800 华南理工大学建筑学院亚热带建筑科学国家重点实验室广东广州510641 广州珠江外资建筑设计院有限公司广东广州510000

有效的遮阳技术措施对于广州地区居住建筑的能耗减少意义重大。本文选取屋顶传热系数、外墙传热系数、综合遮阳系数、外窗传热系数等四个主要要素,以全年平均冷能耗为评价目标,通过正交试验设计出组合方案,并利用DeST软件进行能耗模拟,... 详细信息

有效的遮阳技术措施对于广州地区居住建筑的能耗减少意义重大。本文选取屋顶传热系数、外墙传热系数、综合遮阳系数、外窗传热系数等四个主要要素,以全年平均冷能耗为评价目标,通过正交试验设计出组合方案,并利用DeST软件进行能耗模拟,探究影响该地区住宅建筑能耗的关键性因素。进而以广州地区某住宅西向客厅为例,使用Ecotect软件对五种类型百叶遮阳进行模拟分析,探究各类遮阳的作用效果,最后综合考虑并提出有利于室内光环境和节能的遮阳技术措施。

关键词：广州地区居住建筑遮阳节能率

First-principles study on the mechanical,thermal properties and hydrogen behavior of ternary V-Ni-M alloys

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Journal of Materials Science & Technology 2021年第11期70卷 83-90页

作者： Yanli Lu Yi Wang yifan Wang Meng Gao Yao Chen Zheng Chen State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China

Studying hydrogen behavior in alloys and the mechanical properties of alloys are essential to various practical uses,such as separation membranes,as well as hydrogen embrittlement *** order to further develop the non-Pd-alloy membranes used in hydrogen separation,the mechanical,thermal properties of V_(14)NiM(M=Al,Fe,si,Ti,Zn)and hydrogen solubility and diffusion behaviors of V-based ternary alloys were studied by first principles *** results indicated that the hydrogen solution energies of V-Ni-M are greater than pure *** the mono-vacancy in pure vanadium can capture 6 H atoms while the V-Ni-M alloys can only capture 5 H ***,the V-Ni-M alloys exhibit lower solubility of hydrogen and higher brittleness resistance to embrittlement compared with pure *** the diffusion coefficients of V-Ni-M alloys are smaller than that of pure vanadium thanks to smaller hydrogen *** hydrogen solubility and hydrogen permeability can maintain relatively *** study of mechanical properties suggests that the V-Ni-Ti has the best resistance to deformation and pure vanadium has the best ***,V-Ni-si alloy has the smallest thermal expansion coefficient in the temperature range of 473-723 K,which is the temperature of hydrogen separation,indicating that V-Ni-si is the best for hydrogen separation according to thermal properties.

关键词： Vanadium-based alloys Hydrogen Mechanical properties Diffusion First-principles

Rapid conversion of alkaline bauxite residue through co-pyrolysis with waste biomass and its revegetation potential

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Journal of Environmental Sciences 2023年第5期127卷 102-113页

作者： Yujun Wu Yufei Zhang Qihou Li Jun Jiang yifan Jiang Shengguo Xue School of Metallurgy and Environment Central South UniversityChangsha 410083China Chinese National Engineering Research Center for Control and Treatment of Heavy Metal Pollution Changsha 410083China

The extreme alkalinity of bauxite residue(BR)leads to difficulty with its *** leachate and dust generation during the stacking process can pollute surrounding soil,air and *** this work,co-pyrolysis of bauxite residue and sawdust was applied to rapidly produce a soil-like matrix that met the conditions for plant growth as demonstrated by ryegrass pot *** present study aimed to characterize the detailed changes in physicochemical,mineral weathering,and microbial communities of the pyrolyzed BR with different ratios of saw dust after plant colonization for 2 *** increasing sawdust addition during co-pyrolysis,the pH of BR decreased from 11.21 to 8.16,the fraction of macro-aggregates 0.25-2 mm in the water-stable agglomerates increased by 29.3%,and the organic carbon concentration increased from 12.5 to 320 mg/kg,whilst facilitating the degree of humification,which were all beneficial to its revegetation *** backscattered electron-scanning electron microscope-energy-dispersive X-ray spectrometry(BSE-SEM-EDS)results confirmed the occurrence of sodalite and calcite weathering on aggregate surfaces,and X-ray photoelectron spectroscopy(XPS)results of surface Al and si compounds identified that some weathering products were clay minerals such as ***,bacterial community composition and structure shifted towards typical soil taxonomic *** results demonstrate soil development of treated BR at an early *** technique is a combination of alkalinity regulation and agglomerate construction,which accelerates soil formation of BR,thus proving highly promising for potential application as an artificial soil substitute.

关键词： Bauxite residue Waste sawdust Co-pyrolysis Resource reuse Soil formation

高分辨率探测器短中波红外滤光片的设计及其光谱特性研究

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红外技术 2024年第5期46卷 592-598页

作者：陈永陈昕张一凡胡海波谈婷吕玮东周吉北京空间机电研究所北京100094

短中波红外滤光片是航天光学遥感相机上的关键器件之一。高分辨率探测器的光谱响应由滤光片的光谱特性决定,其中短中波红外占有很大比重,传统方式制备的短中波红外滤光片与理论值存在差距,使得短中波红外滤光片发生光谱角漂或温漂等现象... 详细信息

短中波红外滤光片是航天光学遥感相机上的关键器件之一。高分辨率探测器的光谱响应由滤光片的光谱特性决定,其中短中波红外占有很大比重,传统方式制备的短中波红外滤光片与理论值存在差距,使得短中波红外滤光片发生光谱角漂或温漂等现象,在高分辨率探测器中形成高频和低频光谱混合叠加导致复原光谱失真。本文提出了一种高透过率低漂移高分辨率探测器短中波红外滤光片的设计及研制方法。为了达到短中波红外滤光片特定波长滤光特性的要求(在3.5~4.1μm波段范围内实现98%以上透过率,在2.4~3.35μm、4.25~6.4μm两个波段范围内实现截止),以si材料为滤光片的基底材料,采用模拟染色体遗传交叉算法以带通滤光高低反射率膜堆结构进行了结构迭代设计,薄膜的高折射率材料采用TiO_(2),低折射率材料采用siO_(2),该结构设计使得膜层数量大为减少,通过温漂测试、角漂测试、光谱特性分析及面形测试,短中波红外滤光片达到了前后双波段截止、高通带透过率的目标。环境测试试验表明,短中波红外滤光片膜层与基底材料匹配性适宜、膜层稳定性较高,适用于空间严酷的温度变化、高能粒子辐照环境。

关键词：光学薄膜高分辨率探测器短中波红外光滤光片

太阳上层过渡区极紫外三级次无狭缝成像光谱仪系统设计

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光学学报 2024年第6期44卷 256-268页

作者：沈文杰邢阳光黄一帆彭吉龙代树武王颖朱成林闫雷刘越李林北京理工大学光电学院北京100081 北京卫星环境工程研究所北京100094 北京空间飞行器总体设计部北京100094 北京宇航系统工程研究所北京100076

提出了一款工作在Ne VII 46.52 nm谱线的新型三级次无狭缝成像光谱仪,该仪器采用两个超环面等线距光栅作为衍射元件,其中单个光栅仅工作于一个级次,这解决了现有三级次仪器使用单个光栅同时工作于三个级次的弊端,显著提升了系统校正离... 详细信息

提出了一款工作在Ne VII 46.52 nm谱线的新型三级次无狭缝成像光谱仪,该仪器采用两个超环面等线距光栅作为衍射元件,其中单个光栅仅工作于一个级次,这解决了现有三级次仪器使用单个光栅同时工作于三个级次的弊端,显著提升了系统校正离轴光栅像差的能力,结合光谱数据反演算法可以实现24′×24′视场下的高空间(1.547″)和高光谱分辨率(0.0078 nm)观测。

关键词：成像系统太阳空间观测太阳极紫外成像光谱仪无狭缝超环面等线距光栅