检索结果-南通市图书馆

气溶胶飞行时间质谱仪分析间-二甲苯光氧化颗粒相产物

在线全文

学校读者我要写书评

暂无评论

过程工程学报 2006年第z2期6卷 133-137页

作者：黄明强赵文武郝立庆顾学军王振亚方黎张为俊中国科学研究院安徽光学精密机械研究所环境光谱学实验室安徽合肥230031

在自制的烟雾腔内,用紫外光照射间-二甲苯、亚硝酸甲酯、一氧化氮和清洁空气的混合物,可以启动间-二甲苯和羟基自由基(OH-)的光氧化反应和一系列的后续反应,产生非挥发性和半挥发性有机化合物.半挥发性有机化合物可以在气态和粒子态之... 详细信息

在自制的烟雾腔内,用紫外光照射间-二甲苯、亚硝酸甲酯、一氧化氮和清洁空气的混合物,可以启动间-二甲苯和羟基自由基(OH-)的光氧化反应和一系列的后续反应,产生非挥发性和半挥发性有机化合物.半挥发性有机化合物可以在气态和粒子态之间进行分配,产生二次有机气溶胶粒子.采用实时测量气溶胶粒子粒径大小和化学成分的气溶胶飞行时间质谱仪快速、实时地测量了这些粒子的尺度、它们的分子成分和粒径分布.通过化学分析,得到酚、醛、酮和羧酸等重要的间-二甲苯光氧化产物,为讨论间-二甲苯光氧化反应机理提供了新的信息.

关键词：间-二甲苯光氧化二次有机气溶胶烟雾腔气溶胶飞行时间质谱仪

High-dose dexamethasone regulates microglial polarization via the GR/JAK1/STAT3 signaling pathway after traumatic brain injury

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第9期20卷 2611-2623页

作者： Mengshi Yang Miao Bai Yuan Zhuang Shenghua Lu Qianqian Ge hao li Yu Deng Hongbin Wu Xiaojian Xu Fei Niu Xinlong Dong Bin Zhang Baiyun liu Beijing Tiantan Hospital Capital Medical UniversityBeijingChina Department of Neurology The First Hospital of Tsinghua UniversityBeijingChina Department of Neurotrauma and Beijing Key Laboratory of Central Nervous System Injury Beijing Neurosurgical InstituteCapital Medical UniversityBeijingChina Department of Critical Care Medicine Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Center for Nerve Injury and Repair Beijing Institute of Brain DisordersChina National Clinical Research Center for Neurological DiseasesBeijingChina

Although microglial polarization and neuroinflammation are crucial cellular responses after traumatic brain injury,the fundamental regulatory and functional mechanisms remain insufficiently *** potent anti-inflammato ry agents,the use of glucoco rticoids in traumatic brain injury is still controversial,and their regulatory effects on microglial polarization are not yet *** the present study,we sought to determine whether exacerbation of traumatic brain injury caused by high-dose dexamethasone is related to its regulatory effects on microglial polarization and its mechanisms of *** vitro cultured BV2 cells and primary microglia and a controlled cortical impact mouse model were used to investigate the effects of dexamethasone on microglial ***,dexamethasone,RU486(a glucocorticoid receptor antagonist),and ruxolitinib(a Janus kinase 1 antagonist)were ***-sequencing data obtained from a C57BL/6 mouse model of traumatic brain injury were used to identify potential targets of *** Morris water maze,quantitative reverse transcription-polymerase chain reaction,western blotting,immunofluorescence and confocal microscopy analysis,and TUNEL,Nissl,and Golgi staining were performed to investigate our ***-throughput sequencing results showed that arginase 1,a marker of M2 microglia,was significantly downregulated in the dexamethasone group compared with the traumatic brain injury group at3 days post-traumatic brain *** dexamethasone inhibited M1 and M2 microglia,with a more pronounced inhibitory effect on M2microglia in vitro and in *** receptor plays an indispensable role in microglial polarization after dexamethasone treatment following traumatic brain ***,glucocorticoid receptor activation increased the number of apoptotic cells and neuronal death,and also decreased the density of dendritic spines.A possible downstream receptor signaling mechanism is th

关键词： apoptosis BV2 microglia dexamethasone glucocorticoid receptor glucocorticoids innate immune system microglial polarization neuroinflammation primary microglia traumatic brain injury

在线全文

学校读者我要写书评

暂无评论

分布式交互仿真技术综述

系统仿真学报 1996年第3期8卷 1-5,13页

作者：王锦卿杜政欧阳伶俐郝江波刘青李向阳北京计算机应用和仿真技术研究所

本文介绍了ＤＩＳ的概念和应用，对ＳＩＭＮＥＴ项目作了概要的描述。

关键词：分布式交互仿真仿真网络分布式网络仿真

Trinuclear gold-catalyzed site-selective alkylation of peptides

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2025年第1期 249-256页

作者： qing-Yun Fang Chengyihan Gu Yinghan Chen Wencheng Yan Yong liang Weipeng li Chengjian Zhu Jie Han Jin Xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center (Chem BIC) School of Chemistry and Chemical Engineering Nanjing University Green Catalysis Center College of Chemistry Zhengzhou University State Key Laboratory of Natural Medicines China Pharmaceutical University

Selective modification of peptides has always been a challenging issue. The selective alkylation of peptides can alter the biological activity and physical properties of molecules, and it has gained significant research interest. We herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis. A wide range of structurally diverse primary, secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with the α-C(sp3)–H in glycine residue of peptides. This protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups. A series of relay transformations to construct cyclic peptides, to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic practicality. In addition, mechanistic studies and density functional theory(DFT) calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET) mechanism.

关键词：

同方期刊数据库

巯基修饰单链DNA在纳米金薄膜电极上自组装、杂交和取向的电化学交流阻抗谱

在线全文

学校读者我要写书评

暂无评论

应用化学 2010年第8期27卷 970-977页

作者：魏旭郝青丽陆路德汪信杨绪杰南京理工大学材料化学实验室南京210094

利用电化学交流阻抗技术对SH-ssDNA在纳米金薄膜电极表面的自组装、杂交和取向进行了系统表征。探讨了SH-ssDNA的组装时间、浓度和链长对其自组装的影响,自组装15h时电荷传递电阻Rct最大,表面覆盖率最高;研究了SH-ssDNA的浓度、链长以... 详细信息

利用电化学交流阻抗技术对SH-ssDNA在纳米金薄膜电极表面的自组装、杂交和取向进行了系统表征。探讨了SH-ssDNA的组装时间、浓度和链长对其自组装的影响,自组装15h时电荷传递电阻Rct最大,表面覆盖率最高;研究了SH-ssDNA的浓度、链长以及与互补DNA的杂交方式对杂交反应的影响。结果发现,随着单链浓度的增加,杂交后Rct的变化值逐渐降低,当SH-ssDNA为5μmol/L时Rct值比杂交前增加了16%。通过对阻抗谱数据模拟和分析,表明SH-ssDNA以垂直竖立取向在金电极表面形成均匀致密单分子层,杂交效率与SH-ssDNA的覆盖率密切相关。

关键词：交流阻抗谱 SH-ssDNA 自组装杂交取向

在线全文

学校读者我要写书评

暂无评论

导电聚苯胺掺杂离子互换研究

南京理工大学学报 2010年第3期34卷 376-379,400页

作者：郝青丽严贞贞周倩汪信陆路德杨绪杰南京理工大学软化学与功能材料教育部重点实验室江苏南京210094

为了研究聚苯胺(PANI)掺杂离子之间的交换,通过电化学方法分别在金电极上合成了樟脑磺酸(CSA)和盐酸(HCl)掺杂的PANI膜。采用循环伏安法(CV)、电化学阻抗法(EIS)、扫描电子显微镜(SEM)、拉曼光谱法(Raman)研究了两种离子掺杂的PANI在CSA... 详细信息

为了研究聚苯胺(PANI)掺杂离子之间的交换,通过电化学方法分别在金电极上合成了樟脑磺酸(CSA)和盐酸(HCl)掺杂的PANI膜。采用循环伏安法(CV)、电化学阻抗法(EIS)、扫描电子显微镜(SEM)、拉曼光谱法(Raman)研究了两种离子掺杂的PANI在CSA和HCl溶液中的掺杂离子互换。结果表明:离子半径较小的掺杂离子Cl-可以较容易地将PANI中的半径大的掺杂离子CSA-交换出,而反之较难;聚苯胺膜的形貌在掺杂离子交换前后未发生太大变化,具有一定的形貌"记忆"效应。

关键词：掺杂离子电化学离子互换聚苯胺循环伏安

Double [5]carbohelicene: facile synthesis, chiroptical properties,isomerization study, and lasing application

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2025年第1期 233-240页

作者： Peipei liu Yantong li Meng-Xiang Wu hao Kang Xiao-li Zhao lin Xu linlin liu Xiaodong li Junfeng Fang Zhiwei Fang Ya Cheng Hai-Bo Yang Huakang Yu Xueliang Shi State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University School of Physics and Optoelectronics South China University of Technology Institute of Polymer Optoelectronic Materials & Devices State Key Laboratory of Luminescent Materials & Devices South China University of Technology School of Physics and Electronic Science Engineering Research Center of Nanophotonics & Advanced Instrument Ministry of EducationEast China Normal University State Key Laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University

Double carbohelicenes have attracted considerable attention due to their aesthetic structures, distinct π-conjugation extension, inherent chirality, and intriguing optical and electronic properties. Herein, the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties, isomerization process and lasing application is presented. 1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key intermediate. It is worth noting that1 existed as two diastereomers 1-PP/MM and 1-PM, which were successfully isolated and unambiguously confirmed by Xray crystallography. The optical resolution of the racemic 1-PP/MM was successfully achieved by chiral-phase highperformance liquid chromatography（HPLC）, and 1-PP and 1-MM were characterized by circular dichroism. Interestingly, it was found that 1-PP/MM could be completely isomerized to 1-PM upon heating, and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated. 1-PM exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%. Consequently, we can showcase the lasing application of 1-PM by doping with epoxy resin to assemble a bottle microlaser spontaneously, which the lasing wavelength is 796.6 nm at a threshold of 0.8 m J cm-2. We believe that our studies, including the facile synthesis methodology, detailed isomerization studies, and lasing application, will shed some light on the design and synthesis of novel carbohelical systems with more functions.

关键词：

同方期刊数据库

甲苯与氯原子光氧化产生二次有机气溶胶粒子实时探测研究

在线全文

学校读者我要写书评

暂无评论

过程工程学报 2006年第z2期6卷 123-126页

作者：赵文武黄明强郝立庆郭晓勇顾学军王振亚方黎张为俊中国科学研究院安徽光学精密机械研究所环境光谱学实验室安徽合肥230031

在烟雾腔内,用紫外光照射甲苯、氯气、一氧化氮和空气的混合物,启动甲苯和氯原子的光氧化反应和一系列的后续反应,产生非挥发性和半挥发性有机化合物.半挥发性有机化合物可以在气态和粒子态之间进行分配,产生二次有机气溶胶粒子.用实验... 详细信息

在烟雾腔内,用紫外光照射甲苯、氯气、一氧化氮和空气的混合物,启动甲苯和氯原子的光氧化反应和一系列的后续反应,产生非挥发性和半挥发性有机化合物.半挥发性有机化合物可以在气态和粒子态之间进行分配,产生二次有机气溶胶粒子.用实验室自制的气溶胶飞行时间质谱仪实时测量这些粒子产物的分子成分和粒径分布,并初步探讨了这些组分的可能反应机理.

关键词：甲苯光氧化二次有机气溶胶气溶胶飞行时间质谱仪

用激光解吸附电离法对三甲苯生成二次有机气溶粒子的分析

在线全文

学校读者我要写书评

暂无评论

光学技术 2008年第4期34卷 544-546页

作者：赵文武黄明强郝立庆郭晓勇顾学军王振亚方黎张为俊中国科学院安徽光学精密机械研究所环境光谱学实验室合肥230031

利用实验室烟雾腔,在不同的实验条件下研究了由羟基启动的三甲苯光氧化反应所产生的二次有机气溶胶,采用激光解吸附技术和气溶胶飞行时间质谱仪测量了产物的化学组分和粒子的粒径分布。结果表明:随着反应物三甲苯浓度的增加,所生成的二... 详细信息

利用实验室烟雾腔,在不同的实验条件下研究了由羟基启动的三甲苯光氧化反应所产生的二次有机气溶胶,采用激光解吸附技术和气溶胶飞行时间质谱仪测量了产物的化学组分和粒子的粒径分布。结果表明:随着反应物三甲苯浓度的增加,所生成的二次有机气溶胶粒子数量增多;随着反应时间的延长,生成的粒子数目也增加,但是反应到一段时间后,检测到的粒子数目几乎保持不变;光照强度的增加有利于二次有机气溶胶的生成;通过对产物的化学成分分析,说明了在二次有机光氧化产物中粒子相产物主要是芳香的环保留产物、非芳香环保留产物和环断裂产物。

关键词：光化学三甲苯光氧化二次有机气溶胶(SOA) 激光解吸附电离