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Two-photon spectroscopic behaviors and photodynamic effect on the BEL-74.2 cancer cells of the new chlorophyll photosensitizer

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Science China Chemistry 2008年第6期51卷 529-538页

作者： ZHAO PeiDe1,2,CHEN Ping1,TANG GuoQing1,LIU JinWei2,LIN Lie1,GUO Peng1,YU Qing2, YAO JianZhong3.MA DongMing4.ZHANG GuiLan1 & CHEN WenJu1 1 Key Laboratory of Optoelectronic Information Science and Technology,Ministry of Education,institute of modern Optics,Nankai {3.,Tianjin 3.0071,China 2 Department of {3.,Hebei {3. of Technology,Tianjin 3.013.,China 3.College of Pharmacy,Second Military Medical {3.,shanghai 2.043.,China 4.Tianjin College of the Traditional Chinese Medicine,Tianjin 3.0193.China Key Laboratory of Optoelectronic Information Science and Technology Ministry of Education Institute of Modern Optics Nankai University Tianjin China Department of physics Hebei University of Technology Tianjin China College of Pharmacy Second Military Medical University Shanghai China Tianjin College of the Traditional Chinese Medicine Tianjin China

The spectroscopic properties of a new chlorophyll derivate photosensitizer (CDP) are studied under the excitation wavelengths at 800 and 4.0 nm using femtosecond pulses from a Ti: sapphire laser. The damaging effect of CDP on the BEL-74.2 cancer cells is also investigated upon two-photon illumination at 800 nm. The normalized fluorescence spectra of CDP in tetrahydrofuran (THF) show that two-photon and one-photon spectra have the same distributions and the same emission bands (675 nm). The lifetimes of two- and one-photon induced fluorescence of this molecule are of the order of 5.0 ns. By comparing the data it is shown that there is some difference between the two lifetimes, but the difference is less than one nanosecond. The two-photon absorption cross section of the molecule is also measured at 800 nm and estimated as about σ'_2 ≈ 3..5x10^(-50)cm^4.s·photon^(-1). The results of two-photon photodynamic therapy (TPPDT) tests show that CDP can kill all of the tested cancer cells according to the usual Eosine assessment. Our results indicate that the two-photon-induced photophysical, photochemical and photosensitizing processes of CDP may be basically similar to those of one-photon excitation. These behaviors of the sample suggest that one may find other possible methods to estimate some photosensitizers' effects in details such as their distribution in cells and the reactive targets of the sub-cellular parts of some tumor cells via two-photon excitation techniques.

关键词： photosensitizer chlorophyll derivate two-photon fluorescence two-photon absorption cross-section TPPDT BEL-74.2 cell

Preparation of InSb nanocrystals embedded in SiO_2 thin films

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Chinese Science Bulletin 1998年第19期43卷 1610-1615页

作者： ZHU Kaigui 1, SHI Jianzhong 1, WEI Yanfeng 2 and ZHANG Lide 1 1. institute of Solid State physics, Chinese Academy of Science, Hefei 23.03., China 2. State Key Laboratory of Surface physics,{3.,{4., China institute of Solid State physics Chinese Academy of Science Hefei China State Key Laboratory of Surface physics Fudan University Shanghai China

InSb nanocrystals embedded in SiO 2 thin films were prepared by rf magnetron cosputtering technique. THe observation by transmission electron microscope showed that InSb nanocrystals dispersed uniformly in SiO-2 matrices. InSb nanocrystals with different sizes can be obtained by changing the annealing condition. The average size of InSb nanocrystals depended on annealing temperature and time, but not on the t 1/3.rules. X-ray photoelectron spectroscopy and X-ray diffraction were also applied to the analyses of the composite thin films.

关键词： InSb nanocrystals radio-frequency sputtering quantum confinement.

Speciation of the elements and compositions on the surfaces of dust storm particles:The evidence for the coupling of iron with sulfur in aerosol during the long-range transport

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Chinese Science Bulletin 2005年第8期50卷 738-744页

作者： ZHANG Xingying1,2, ZHUANG Guoshun1,2,3. CHEN Jianmin2 & XUE Huaxin2 1. Center for Atmospheric Environment Study, Department of Chemistry, Beijing Normal university, Beijing 100875, China 2. Center for Atmospheric Chemistry Study, Department of Environ- mental Science and Engineering, fudan university, shanghai 2.043., China 3. LAPC/NZC,{3. of Atmospheric {4., NZC/LAPC, Chinese Academy of Sciences, Beijing 100029, China Center for Atmospheric Environment Study Department of Chemistry Beijing Normal University Beijing 100875 China Center for Atmospheric Chemistry Study Department of Environmental Science and Engineering Fudan University Shanghai 200433 China LAPC/NZC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The speciation of the elements on the surface of the particles collected during dust storm and non-dust storm in Beijing and Inner Mongolia was studied by XPS. The ma- jor species of iron on the surface were oxides, sulfate, silicate, FeOOH and minor part sorbed on SiO2/Al2O3. Sulfate is the dominant species of sulfur on the surface. SiO2 and Al2O3.are the main components of Si and Al on the surface respectively. One of the most important findings was that the Fe(II) (FeS and FeSO4. produced could account for up to 4..3. and 4..6% of the total Fe on the surface in the aerosol sample collected at that night and next day of the “peak” time of the dust storm occurring on March 20, 2002, while Fe2(SO4.3. one of the Fe(III) species on the surface decreased from 67.1% to 4..5% and 4..0% respectively. Both S and Fe en- riched on the surface of aerosol particles. Fe(II) accounted for 1.3.?5.3. of total Fe in bulk aerosol samples during dust storm. These results provided strong evidence to sup- port the hypothesis of the coupling between iron and sulfur in aerosols during the long-range transport, which would have important impact on the global biogeochemical cycle.

关键词：物种形成原理 XPS 大气悬浮物 Fe-S结合粒子集合

Decomposition of CF_3.I by corona discharge

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Journal of Environmental Sciences 1997年第1期9卷 95-99页

作者： Liu Zhengchao Pan Xunxi Dong Wenbo Hou Huiqi Environmental Science institute,fudan university,{3. {4.,ChinaZhang Zhenman Hou Jian Yu Yong Li Changlin Department of physics Ⅱ,fudan university,{3. {4.,China

In this paper pulsed corona discharge is shown to be effective for the decomposition ofCFCl（Freon-13..The pressure of CFCl was 2.67×10Pa,after discharged for 2 min,3..5% ofCFCl was *** products were mainly CF,Cland *** yield increased byadding Oor *** the same conditions,more than 94. decomposition yield was obtained if5.3.×10Pa Oor air was *** composition of products became CFO,Cland *** partial pressure of Oor air reached 1 arm,the decomposition yield decreased to 54.5% and 4..5% respectively.

关键词： decomposition Freon-13 plasma.

Determination of Shallow Impurity Concentration in Detector-grade Silicon by FT-IR Spectroscopy at 4.2K

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Rare Metals 1989年第4期9卷 54-58页

作者： Zhang, Jichang Wu, Jiangen Qu, Fengyuan Ye, Hongjuan Xiao, Jincai Yu, Zhiyi Lu, Wei Tongji Univ China

A Nicolet-200SXV FT-IR spectrometer combined with an exciting light set-up has been applied to determine the shallow impurity concentration in detector-grade silicon. The detection sensitivity of boron concentration is high up to 7.8 × 10-12. The calibration curve of boron concentration in high-purity silicon has been obtained, from which the experimental value of calibration factor of boron concentration in silicon is demonstrated to be 1.15 × 1013.cm-1.

关键词： Boron Trace Analysis Radiation Detectors Silicon Spectrometers, Infrared Sensitivity Spectroscopy, Infrared Low Temperature

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二能级系统的布居囚禁现象

物理学报 2001年第12期50卷 2335-2340页

作者：龙德顺宁西京复旦大学现代物理研究所上海200433

采用缀饰原子模型 ,以解析方式研究了二能级系统布居囚禁现象 ,给出了实现布居囚禁现象的条件 ,并通过解析公式计算演示了各种条件下布居囚禁的不同行为 .

关键词：布居囚禁二能级系统缀饰原子模型原子激发态

VERTICAL HEREDITY VS. HORIZONTAL GENE TRANSFER: A CHALLENGE TO BACTERIAL CLASSIFICATION

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Journal of Systems Science & Complexity 2003年第3期16卷 307-314页

作者： HAO Bailin(institute of Theoretical physics, Academy of Chinese Sciences, Beijing 100080, China Senior International Fellow of the Santa Fe institute T-Life Research Center,{3.,{4. 2.043., China)QI Ji(institute of Theoretical physics, Beijing 100080, China) institute of Theoretical physics Academy of Chinese Sciences 北京 100080 institute of Theoretical physics Chinese Academy of Sciences 北京 100080

The diversity and classification of microbes has been a long-standing *** phylogeny of the prokaryotes based on comparison of the 16S rRNA sequences of the small ribosomal subunit has led to a reasonable tree of life in the late 1970s. How-ever, the availability of more and more complete bacterial genomes has brought about complications instead of refinement of the tree. In particular, it turns out that different choice of genes may tell different history. This might be caused by possible horizontal gene transfer (HGT) among species. There is an urgent need to develop phylogenetic methods that make use of whole genome data. We describe a new approach in molecular phylogeny,namely, tree construction based on K-tuple frequency analysis of the genomic *** aside the technicalities, we emphasize the transition from randomness to determin-ism when the string length K increases and try to comment on the challenge mentioned in the title.

关键词： prokaryote phylogeny horizontal gene transfer fitness compositionaldistance

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类钠离子的电子碰撞电离截面

物理学报 2001年第8期50卷 1475-1480页

作者：齐静波陈重阳王炎森复旦大学现代物理研究所上海200433

利用相对论修正扭曲波玻恩交换近似 ,计算了 8个类钠离子的电子碰撞直接电离和激发自电离截面 .基于这些结果 ,给出了计算类钠等电子系离子 (18≤Z≤ 3.)直接电离和激发自电离截面的高精度拟合公式 .计算结果与现有的实验值和其他理论... 详细信息

利用相对论修正扭曲波玻恩交换近似 ,计算了 8个类钠离子的电子碰撞直接电离和激发自电离截面 .基于这些结果 ,给出了计算类钠等电子系离子 (18≤Z≤ 3.)直接电离和激发自电离截面的高精度拟合公式 .计算结果与现有的实验值和其他理论值比较。

关键词：电离截面组态相互作用扭曲波玻恩交换近似拟合公式电子碰撞类钠离子

Wavefront reconstruction of Fresnel diffraction field by optical methods and digital algorithm

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Chinese Journal of Lasers 1993年第3期 81-86页

作者： Yue Zhang, Songlin Zhuang (shanghai institute of Optical Instruments, shanghai 200093.China)Keshu Xu ({3. Department,{4.,shanghai 2.043.,China)

The experimental methods for measuring the phase distribution of Fresnel diffraction field by using interference and polarization information are given in this paper. An effective algorithm for phase retrieval under F... 详细信息

关键词： interference polarization iteration