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分光技术在自由电子激光结合里德堡态氢原子飞行时间谱装置中的应用 被引量:1
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作者 常尧 贺志刚 +11 位作者 罗子杰 周家米 张志国 陈志超 杨家岳 余永 李钦明 车丽 吴国荣 王兴安 杨学明 袁开军 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2020年第2期139-144,I0002,共7页
本文描述了一种应用于自由电子激光结合高里德堡态氢原子飞行时间谱装置中的分光方法,以及该方法应用于小分子(如2S)光解动力学研究中的必要性.拉曼-α辐射(121.6 nm),用作H原子产物探测的激光,是在Kr/Ar气介质中利用四波混频产生的.利... 本文描述了一种应用于自由电子激光结合高里德堡态氢原子飞行时间谱装置中的分光方法,以及该方法应用于小分子(如2S)光解动力学研究中的必要性.拉曼-α辐射(121.6 nm),用作H原子产物探测的激光,是在Kr/Ar气介质中利用四波混频产生的.利用透镜对不同波长的光有不同的折射率,四波混频后的混合光在经过一片离轴的氟化锂透镜后,121.6 nm的激光将会与212.6和845 nm在空间上分开.在激光到达反应中心前利用挡板挡住212.6和845 nm的激光,只让121.6 nm的光经过反应中心,从而消除212.6 nm激光产生的背景信号对实验的干扰.结合自由电子激光,成功地研究了H2S在122.95 nm波长下的光解动力学,采集到了产物时间飞行谱.本文展示了转换得到的产物总平动能谱,解离机理与121.6 nm波长下的结果相似.实验结果显示,该方法成功地解决了分子在VUV波段进行光解动力学研究的难题,消除了这些分子在紫外光波段因为强烈吸收而产生的背景信号. 展开更多
关键词 光解动力学 自由电子激光 分光系统
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痛泻要方对急性放射性肠炎大鼠肠组织的防护作用及机制 被引量:5
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作者 杨成 焦旸 +4 位作者 杨家悦 周志毅 吴小青 李雅琳 占强 《世界华人消化杂志》 CAS 2018年第15期898-903,共6页
目的初步研究痛泻要方对急性放射性肠炎(radiation enteritis,RE)大鼠肠组织的防护作用及机制.方法随机将48只♂SD大鼠分为4组:A组为正常对照组(n=12)、B组为模型照射组(n=12)、C组为痛泻要方组(n=12)、D组为谷氨酰胺组(n=12);A组不予... 目的初步研究痛泻要方对急性放射性肠炎(radiation enteritis,RE)大鼠肠组织的防护作用及机制.方法随机将48只♂SD大鼠分为4组:A组为正常对照组(n=12)、B组为模型照射组(n=12)、C组为痛泻要方组(n=12)、D组为谷氨酰胺组(n=12);A组不予任何处理,其余三组均以高能X线直线加速器给予10 Gy全腹腔照射.造模成功后第1天,A组和B组给予蒸馏水,C组给予中药痛泻要方,D组给予谷氨酰胺,各组均连续灌胃7 d.每日观察大鼠一般状况、排便情况及体重变化.各组均于灌胃结束后6 h取空肠组织,光镜下观察肠组织形态学变化.检测空肠组织匀浆一氧化氮(nitric oxide,NO)的含量,ELISA法测定空肠黏膜炎性因子白介素(interleukin,IL)-6、IL-10、肿瘤坏死因子-α(tumor necrosis factorα,TNF-α)的蛋白含量.结果灌胃结束后,除B组于造模第3天死亡1只外,其余各组均无死亡.C组和D组大鼠的一般状况及黏液血便均有不同程度改善,体重增加较B组明显(P<0.05).与B组比较,C组和D组大鼠的NO、IL-6及TNF-α含量均出现下降(P<0.05).C组和D组大鼠的IL-10含量较B组大鼠明显升高,差异均有显著统计学意义(P<0.01).结论痛泻要方对急性RE大鼠的肠黏膜具有防护作用,其机制可能与降低空肠NO、IL-6及TNF-α活性,提高IL-10含量,减轻肠组织炎症反应有关. 展开更多
关键词 痛泻要方 放射性肠炎 炎症反应 防护作用
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An Ion-Pumping Interphase on Graphdiyne/Graphite Heterojunction for Fast-Charging Lithium-Ion Batteries
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作者 Juan An Fan Wang +2 位作者 jia-yue yang Guoxing Li Yuliang Li 《CCS Chemistry》 CSCD 2024年第1期110-124,共15页
The sluggish lithium-ion(Li-ion)transport kinetics in graphite anode hinders its application in fast-charging Li-ion batteries(LIBs).Here,we develop an ionpumping interphase(IPI)on graphdiyne(GDY)/graphite heterojunct... The sluggish lithium-ion(Li-ion)transport kinetics in graphite anode hinders its application in fast-charging Li-ion batteries(LIBs).Here,we develop an ionpumping interphase(IPI)on graphdiyne(GDY)/graphite heterojunction anodes to boost the ionic transport kinetics and enable high-performance,fast-charging LIBs.The IPI changed the ion solvation/desolvation environment by covalent/non-covalent interactions with Li ions or solvents to optimize solid-electrolyte interphase(SEI)and regulate Li-ion transport behavior.We studied the in situ growth of few-layer GDY on graphite surface(GDY/graphite)as the IPI and found that the strong interaction between GDY and Li ions enabled surface-induced modification of the ion solvation behavior and surface-assisted desolvation effect to accelerate the Li-ion desolvation process.A functional anion-derived SEI layer with improved Li-ion conductivity was created.Together with the generated built-in electric field at GDY/graphite hetero-interface self-pumping Li ions to intercalate into the graphite,the Li-ion transport kinetics was significantly enhanced to effectively eliminate Li plating and large voltage polarization of the graphite anodes.A fast Li intercalation in GDY/graphite without Li oversaturation at the edge of the graphite was directly observed.The superior performance with high capacity(139.2 mA h g^(-1))and long lifespan(1650 cycles)under extremely fast-charging conditions(20 C,1 C=372 mA g^(-1))was achieved on GDY/graphite anodes.Even at low temperatures(-20℃),a specific capacity of 128.4 mA h g^(-1) was achieved with a capacity retention of 80%after 500 cycles at a 2 C rate. 展开更多
关键词 extreme fast-charging lithium-ion batteries lithium-ion transport kinetics ion-pumping interphase graphdiyne/graphite heterojunction
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Origins of three-dimensional charge and two-dimensional phonon transports in Pnma phase PbSnSe_(2)thermoelectric crystal
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作者 Tianyu Wang Xinlei Duan +6 位作者 Hao Zhang Jinlong Ma Hangtian Zhu Xin Qian jia-yue yang Te-Huan Liu Ronggui yang 《InfoMat》 SCIE CSCD 2023年第12期65-76,共12页
Recently,PbSnSe_(2)alloy was found to exhibit a large hysteresis effect on transport properties,demonstrating its significant potential for thermoelectric applications.Using ab initio approaches,we studied the carrier... Recently,PbSnSe_(2)alloy was found to exhibit a large hysteresis effect on transport properties,demonstrating its significant potential for thermoelectric applications.Using ab initio approaches,we studied the carrier transport properties of PbSnSe_(2)crystal,which is a special case of the alloy with the shortest-range order.A peak power factor of 134.2μW cm^(-1)K^(-2)was found along the crossplane direction in the n-type PbSnSe_(2)at a doping concentration of 7×10^(20)cm^(-3)at 700 K.This high power factor originates from delocalized p electrons between intra-plane Pb-Se pairs and between cross-plane Sn-Se pairs that can build up transport channels for conducting electrons,leading to a high electrical conductivity of 5.9×10^(5)S m^(-1).Introducing Pb atoms into Pnma phase SnSe can decrease the phonon group velocities and enhance the phonon-phonon scatterings,leading to a low thermal conductivity of 0.53 W m^(-1)K^(-1)at 700 K along the cross-plane direction.The calculated peak ZT of~3 along the cross-plane direction at an n-type doping concentration of around 5×10^(19)cm^(-3),which represents a theoretical upper limit for an idealized PbSnSe_(2)crystal.This work interprets the origins of three-dimensional charge and two-dimensional phonon transport behavior in PbSnSe_(2)and demonstrates that such crystals are promising high-performance thermoelectric semiconductors. 展开更多
关键词 3D charge and 2D phonon transports ab initio calculations PbSnSe_(2) thermoelectric properties
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