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A reinvestigation of low molecular weight components in SOA produced by cyclohexene ozonolysis

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Nuclear Science and Techniques 2018年第11期29卷 238-246页

作者： Jun Chen Zhao-Hui Li Ye-Peng Yu Xuan Lin Hang Zhang Yan-Bo Li Huan-Huan Wang Rui-Rui Sun Qing-Hui Meng Chao-Qun Huang Xiao-Bin Shan Fu-Yi liu Chang-Jin Hu Wei-Jun Zhang liu-si sheng National Synchrotron Radiation Laboratory School of Nuclear Science and TechnologyUniversity of Science and Technology of China Laboratory Medical Optical and Mass Spectrometry Center of Medical Physics and TechnologyHefei Institutes of Physical ScienceChinese Academy of Sciences Laboratory of Atmospheric Physico-Chemistry Anhui Institute of Optics and Fine MechanicsChinese Academy of Sciences School of Environmental Science and Optoelectronic Technology University of Science and Technology of China

The ozonolysis of cyclohexene is an important model system for understanding the more complex reaction of O_3 with monoterpenes; however, many previous studies have come to qualitatively different conclusions about the composition of the secondary organic aerosol(SOA)formed in this system. In the present study, the composition of the SOA produced by cyclohexene ozonolysis in the absence of seed aerosols has been investigated online and off-line using synchrotron-based thermal desorption/tunable vacuum ultraviolet photoionization time-of-flight aerosol mass spectrometry(TD-VUV-TOF-PIAMS) in conjunction with a custom-built smog chamber. On the basis of the molecular ions observed by mass spectrometry at 11.5 e V, it was found that dicarboxylic acids, dialdehydes, and cyclic anhydrides are the predominant low molecular weight components in the particle phase. The results also indicated that TD-VUV-TOF-PIAMS coupled with filter sampling is a potentially useful tool for the investigation of SOA composition both in the field and in the laboratory.

关键词： Cyclohexene Ozonolysis SOA Smog chamber Aerosol mass spectrometry

VUV Photoionization Study of the Allyl Radical from Premixed Gasoline/Oxygen Flame

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Chinese Journal of Chemical Physics 2006年第1期19卷 25-28页

作者： Rui Yang Bin Yang Chao-qun Huang Li-xia Wei Jing Wang Xiao-bin Shan liu-si sheng Yun-wu Zhang Fei Qi Chun-de Yao Qi Li Qing Ji National Synchrotron Radiation Laboratory University of Science and Technology of China Hefei230029 China State Key Laboratory of Engines Tianjin University Tianjin 300072 China

The allyl radical has been observed in a low-pressure premixed gasoline/oxygen/argon flame by using tunable vacuum ultraviolet photoionization mass spectrometry, The ionization potential of the allyl radical is derived to be （8.13 ±0.02） eV from photoionization efficiency curve, In addition, a high level ab initzo Gaussian-3 （G3） method was used to calculate the energies of tile radical and its cation. The calculated adiabatic ionization potential is 8.18 eV, which is in excellent agreement with the experimental value. The result is helpful for identifying the allyl radical formed from other flames and for understanding the mechanism of soot formation.

关键词： Ally radical Photoionization efficiency curve Flame

Investigation of Vacuum Ultraviolet Photoionization of Methylcyclohexane in Energy Region of 9-15.5 eV

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Chinese Journal of Chemical Physics 2020年第3期33卷 296-302,I0002页

作者： Hang Zhang Yan-bo Li Long Zhu Jun Chen Ye-peng Yu Zhao-hui Li Xuan Lin Xiao-bin Shan Fu-yi liu liu-si sheng National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China

Vacuum ultraviolet(VUV)photoionization and photodissociation of methylcyclohexane have been studied utilizing a reflectron time-of-flight mass spectrometer(RTOF-MS)with synchrotron radiation *** efficiency curves(PIEs)of molecule ion C7H14^+ and fragment ions C7H13^+,C6H11^+,C6H10+,C5H10^+,C5H9^+,C4H8^+,C4H7^+,and C3H5^+ were *** ionization energy of methylcyclohexane was measured to be(9.80±0.03)eV,and appearance energies of fragment ions were determined from the *** structures of transitional states,intermediates and product ions were characterized at the B3LYP/6-31G(d)level and the energies were calculated using G3B3 *** channels of dominating fragment ions were *** hydrogen migrations and carbon ring-opening were the foremost processes in fragmentation pathways of methylcyclohexane.

关键词： Methylcyclohexane Photoionization and photodissociation Synchrotron radiation source Reflectron time-of-flight mass spectrometer

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数控G代码解释器和仿真模块的设计与实现

机械设计与制造 2012年第1期 172-174页

作者：刘思胜李松生陈萍上海大学机械与自动化学院上海200072

设计了一种G代码解释器和图形仿真于一体的数控仿真检验系统。该系统以Vc++为开发工具,根据GALIL运动控制卡的协议编辑了G代码解释器。此解释器除了一般的解释和检查的作用外,较以往解释器开发编译了更多的G代码,并结合OpenGL技术开发... 详细信息

设计了一种G代码解释器和图形仿真于一体的数控仿真检验系统。该系统以Vc++为开发工具,根据GALIL运动控制卡的协议编辑了G代码解释器。此解释器除了一般的解释和检查的作用外,较以往解释器开发编译了更多的G代码,并结合OpenGL技术开发了数控三维仿真加工过程。通过选择OpenGL作为图形开发工具,建立了一个数控仿真系统,通过对输入加工代码的图形验证,实现了刀具运动轨迹仿真和材料去除过程仿真,达到了实时仿真的要求。验证了该系统的整体可行性。

关键词： Vc++ G代码解释器 OpenGL仿真

Experimental and Theoretical Study on Dissociative Photoionization of Cyclopentanone

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Chinese Journal of Chemical Physics 2018年第5期31卷 619-625,735页

作者： Zhao-hui Li Ye-peng Yu Xuan Lin Jun Chen Hang Zhang Yan-bo Li Huan-huan Wang Qing-hui Meng Rui-rui Sun Xiao-bin Shan Fu-yi liu liu-si sheng National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China

The dissociative photoionization of cyclopentanone was investigated by means of a reflectron time-of-flight mass spectrometer(RTOF-MS)with tunable vacuum ultraviolet synchrotron radiation in the photon energy range of 9.0~15.5 *** photoionization efficiency(PIE)curves for molecular ion and fragment ions were *** ionization energy of cyclopentanone was determined to be 9.230.03 *** ions from the dissociative photoionization of cyclopentanone were identified as C5H7O+,C4H5O+,C4H8+/C3H4O+,C3H3O+,C4H6+,C2H4O+,C3H6+,C3H5+,C3H4+,C3H3+,C2H5+and C2H4+.With the aid of the ab initio calculations at theωB97X-D/6-31+G(d,p)level of theory,the dissociative mechanisms of C5H8O+are *** opening and hydrogen migrations are the predominant processes in most of the fragmentation pathways of cyclopentanone.

关键词： Cyclopentanone Synchrotron radiation Photoionization and dissociation ab initio calculations

Photoionization and Dissociation Study of 2-Methyl-2-propen-1-ol:Experimental and Theoretical Insights

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Chinese Journal of Chemical Physics 2019年第3期32卷 306-312,I0001页

作者： Ye-peng Yu Zhao-hui Li Xuan Lin Jun Chen Hang Zhang Yan-bo Li Huang-huang Wang Rui-rui Sun Qing-hui Meng Xiao-bin Shan Fu-yi liu liu-si sheng National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China

The photoionization and dissociation of 2-methyl-2-propen-1-ol(MPO)have been investigated by using molecular beam experimental apparatus with tunable vacuum ultraviolet synchrotron radiation in the photon energy region of 8.0-15.5 *** photoionization efficiency(PIE)curves for molecule ion and fragment ions:C4H8O^+,C4H7O^+,C3H5O^+,C4H7^+,C4H6^+,C4H5^+,C2H4O^+,C2H3O+,C3H6^+,C3H5^+,C3H3^+,CH3O^+,CHO^+have been measured,and the ionization energy(IE)and the appearance energies(AEs)of the fragment ions have been *** stable species and the first order saddle points have been calculated on the CCSD(T)/cc-pvTZ//B3LYP/6-31+G(d,p)*** combination of theoretical and experimental results,the dissociative photoionization pathways of 2-methyl-2-propen-1-ol are *** migrations within the molecule are the dominant processes in most of the fragmentation pathways of MPO.

关键词： 2-Methyl-2-propen-1-ol Synchrotron radiation Photoionization Vacuum ultraviolet Mass spectrometry

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人工通江湖泊非汛期生态调度方案研究

长江科学院院报 2020年第6期37卷 28-33页

作者：柴朝晖姚仕明刘同宦刘斯盛长江科学院河流研究所武汉430010 长江科学院水利部江湖治理与防洪重点实验室武汉430010 华中农业大学工学院武汉430070

除鄱阳湖和洞庭湖外,长江中下游通江湖泊基本以涵闸形式连通江湖。由于缺乏水体的自然交换,此类湖泊经常出现水质超标的情况,特别是枯水期。以华阳河湖群为例,通过实测资料分析、现场调研、数值模拟研究了其进行生态调度的可行性及具体... 详细信息

除鄱阳湖和洞庭湖外,长江中下游通江湖泊基本以涵闸形式连通江湖。由于缺乏水体的自然交换,此类湖泊经常出现水质超标的情况,特别是枯水期。以华阳河湖群为例,通过实测资料分析、现场调研、数值模拟研究了其进行生态调度的可行性及具体方案。研究结果表明:华阳河湖群TN、TP浓度随水位的升高呈下降趋势,但当湖群水位超过某值(13.5 m)后,浓度下降趋势变缓,且湖群9月下旬多年平均水位高于现行非汛期控制水位,因此,利用华阳和杨湾闸进行湖群非汛期生态调度是可行的。在考虑现行闸门调度方式、江湖关系、确保防洪安全和水环境改善4个原则的基础上,结合数值模拟结果,确定了华阳河湖群非汛期生态调度方案,即利用杨湾闸和华阳闸控制湖区10—12月份水位控制在13 m,1—2月份控制在12.5 m,3—4月份控制在11.8 m。

关键词：通江湖泊江湖关系非汛期生态调度方案水质参数数值模拟泄水时机

Threshold Photoelectron-photoion Coincidence Imaging of Dissociation Dynamic of NO＋ at c3∏（v′=0） State

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Chinese Journal of Chemical Physics 2010年第5期23卷 509-512,621页

作者：孙金大单晓斌刘付轶盛六四唐小锋牛铭理宋磊周晓国刘世林中国科学技术大学国家同步辐射实验室核科学技术学院合肥230029 中国科学技术大学合肥微尺度物质科学国家实验室化学物理系合肥230026

The photodissociation of NO＋ at c3∏（v′=0） state is studied by threshold photoelectron- photoion coincidence imaging method. By some assumptions, the relations between velocity in center of mass （CM） coordinates and most probable center of mass （MPCM） coordinates, time of flight and displacement in the velocity map image of fragment ions are derived using vector addition of velocity and displacement on the condition of perpendicular molecular beam. Using these relations the velocity in CM coordinates, the velocity and angular distri- bution of N＋ fragment ions in MPCM coordinates are obtained and discussed, respectively.

关键词： Threshold photoelectron-photoion coincidence imaging Velocity map imag-ing Nitric oxide Kinetic energy released distribution Angular distribution

Transforming growth factor-beta 1 enhances discharge activity of cortical neurons

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Neural Regeneration Research 2025年第2期20卷 548-556页

作者： Zhihui Ren Tian Li Xueer liu Zelin Zhang Xiaoxuan Chen Weiqiang Chen Kangsheng Li Jiangtao sheng Department of Microbiology and Immunology Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular ImmunopathologyShantou University Medical CollegeShantouGuangdong ProvinceChina Department of Neurosurgery First Affiliated Hospital of Shantou University Medical CollegeShantouGuangdong ProvinceChina

Transforming growth factor-beta 1(TGF-β1)has been extensively studied for its pleiotropic effects on central nervous system *** neuroprotective or neurotoxic effects of TGF-β1 in specific brain areas may depend on the pathological process and cell types ***-gated sodium channels(VGSCs)are essential ion channels for the generation of action potentials in neurons,and are involved in various neuroexcitation-related ***,the effects of TGF-β1 on the functional properties of VGSCs and firing properties in cortical neurons remain *** this study,we investigated the effects of TGF-β1 on VGSC function and firing properties in primary cortical neurons from *** found that TGF-β1 increased VGSC current density in a dose-and time-dependent manner,which was attributable to the upregulation of Nav1.3 *** VGSC current density and Nav1.3 expression were significantly abolished by preincubation with inhibitors of mitogen-activated protein kinase kinase(PD98059),p38 mitogen-activated protein kinase(SB203580),and Jun NH2-terminal kinase 1/2 inhibitor(SP600125).Interestingly,TGF-β1 significantly increased the firing threshold of action potentials but did not change their firing rate in cortical *** findings suggest that TGF-β1 can increase Nav1.3 expression through activation of the ERK1/2-JNK-MAPK pathway,which leads to a decrease in the firing threshold of action potentials in cortical neurons under pathological ***,this contributes to the occurrence and progression of neuroexcitatory-related diseases of the central nervous system.

关键词： central nervous system cortical neurons ERK firing properties JNK Nav1.3 p38 transforming growth factor-beta 1 traumatic brain injury voltage-gated sodium currents