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Chinese Science Bulletin 2014年第34期59卷 4712-4719页

作者： Wenfeng zhao Jie Xie jingquan zhao Beijing National Laboratory for Molecular Sciences (BNLMS) CAS Key Laboratory of Photochemistry Institute of ChemistryChinese Academy of Sciences

State transition and blue-green light-induced fluorescence quenching are two short-term processes in cyanobacteria. The details of their kinetics and the relationship between these processes have not been *** this work, these two processes were studied in the wildtype cyanobacterium Synechocystis PCC 6803 cells as well as in apc D-and apc F-mutants by monitoring their timedependent 77 K fluorescence responses to blue-green light(430–540 nm) at a series of intensities ranging from20–800 l E m-2s-1. The lowest light intensity to induce fluorescence quenching in wild-type cells was160 l E m-2s-1under the selected experimental conditions, while state transition took place at the intensities lower than 160 l E m-2s-1at a conservative level, but at variable rates. The quenching level increased at intensities higher than 160 l E m-2s-1, reaching the maximum level at intensities equal to or higher than 200 l E *** kinetics indicated that both the length of the induction period and time required to reach the maximum level were functions of light intensity. State transitions as well as fluorescence quenching took place in both wildtype and mutant cells, but might involve different mechanisms.

关键词：荧光动力学状态转换野生型光诱导突变体 PCC 集胞藻蓝绿色

Drug-delivery and multifunction possibilities of hypocrellin photosensitizers

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Journal of Innovative Optical Health Sciences 2015年第1期8卷 27-39页

作者： Hong Deng Jie Xie jingquan zhao Beijing National Laboratory for Molecular Sciences(BNLMS)Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences P.O.Box 101No.21st North Street ZhongguancunBeijing 100190P.R.China

Photodynamic therapy(PDT)has been a routine treatment of tumors and some microvascular diseases,but clinically available photosensitizers are still *** all kinds of photo-sensitizers,hypocellins possess the most characteristics of ideal photosensitizers,such as,high photo-activity but low dark toxicity,fast clearance from *** review is focused on two main topics,drug-delivery problem of hypocrellins and how the environment-sensitive fluorescence of bypecrellins was used for recognition of various ***-delivery of hypocrellins was mainly achieved in two strategies一preparing the drugdelivery vehicles and finding quantitatively amphiphilic *** fAuorescence originated from the intramolecular proton transfer is very distinct from other kinds of ***,it was proved that quan-titative hypocrellin ftuorescence could not only reoognize various biomolecules,including proteins,polysaocharides and lipids,but also distinguish the specific binding from nonspedifie binding with some kind of ***,hypocrellin fluorescence was pH *** is known that tumor cells or tses have the features of a large amount of lipid,neonatal collagen,over expression of polysaccharides,and lower pH values compared to normal *** to the relative but not absolute specifcity,further studies on quantitative recognition of various biomolecules at a cellular level,may find a new clue to treat tumors by joint usage of photodynamic diagnosis(PDD)and PDT.

关键词： Hypocrellins photodynamie therapy drug delivery biomolecular recognition

Structure and function of PBS model complex

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Chinese Science Bulletin 1998年第8期43卷 646-649页

作者： Hui Wang jingquan zhao Lijin Jiang Chinese Acad Sci Inst Photog Chem Beijing 100101 Peoples R China

A complex of phycobiliproteins, containing phycoerythrocyanin (PEC), C_phycovyanin (C_PC) and allo_phycocyanin (APC) as well as some linker polypeptides, was reconstructed. The absorption and fluorescence spectra of the complex were compared with those of native phycobilisomes (PBS) and the phycobiliproteins. Based on the measured data, it can be concluded that the complex can be taken as a model of PBS and is an entirely functional group for excitation energy transfer step by step from peripheral PEC to APC. The single terminal emitter feature of the complex makes it favorable for clarifying energy transfer pathways and the kinetics in comparison with native PBS. Further research is carried on in the lab.

关键词： Anabaena variabilis PBS model complex reconstruction excitation energy transfer.

A power and thermal management system for long endurance hypersonic vehicle

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Chinese Journal of Aeronautics 2023年第2期36卷 29-40页

作者： Liang GUO Liping PANG Xiaodong YANG jingquan zhao Desheng MA School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Institute of Artificial Intelligence Beihang UniversityBeijing 100191China

Due to the pneumatic heating and combustion effect,the scramjet engine of hypersonic vehicle faces high temperature *** is necessary to comprehensively consider its thermal management and power generation together.A new Power and Thermal Management System(PTMS)combined with Supercritical Carbon Dioxide(SCO_(2))closed Brayton cycle and fuel vapor turbine is proposed and discussed in this *** new PTMS can meet the cooling requirement of hypersonic vehicle at Mach number 6–7,and avoid the coking and scrapping in the scramjet cooling *** with the PTMS only based on fuel vapor turbine,the new PTMS utilizes the waste heat of scramjet to generate more *** addition,it can reduce the use of fuel sink for cooling,and the additional weight penalty can be compensated for long endurance hypersonic flight.

关键词： Fuel vapor turbine Hypersonic vehicle Power and thermal management system Scramjet Supercritical carbon dioxide

Elsinochrome A photosensitizers:Alternative drugs for photodynamic therapy

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Journal of Innovative Optical Health Sciences 2015年第1期8卷 4-13页

作者： Tinghui Li Hong Deng jingquan zhao Ying Gu Department of Laser Medicine Chinese PLA General HospitalBeijing 100853 People's Republic of China Department of Dermatology 309 Hospital of PLABeijing 100091People's Republic of China Beijing National Laboratory for Molecular Sciences(BNLMS) Key Laboratory of PhotochemistryInstitute of Chemistry Chinese Academy of SciencesBeijing 100190 People's Republic of China

Photodynamic therapy(PDT)has already been a multifunctional modality for various tumors and nontumorous ***,the development of photosensitizers is relatively delayed,compared with the tremendous progress in laser *** A(EA),a per-ylenequinonoid pigment from China,has all the typical advantages of ***-over,singlet oxygen quantum yield of EA is superior to other kinds of photosensitizers and EA could be artifially biosynthesized at present,which make it an alternative candidate for *** review,the photophysics,photochemistry,photobiology and chemical or biological syntheses of EA photosensitizers are brielty ***,the future prospects of EA photosensitizers are also proposed.

关键词： Elsinochrome A photodynamic therapy potochemisty photophysics photobiology

Impact of gravitation on gaseous pollutant source identification

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Chinese Journal of Aeronautics 2013年第2期26卷 261-268页

作者： Pang Liping Zhang Yu Qu Hongquan Hu Tao zhao jingquan School of Aviation Science and Engineering Beihang University College of Information Engineering North China University of Technology

It is necessary to identify a gaseous pollutant source rapidly so that prompt actions can be taken, but this is one of the difficulties in the inverse problem areas. In this paper, an approach to identifying a sudden continuous emission pollutant source based on single sensor information is developed to locate a source in an enclosed space with a steady velocity field. Because the gravity has a very important influence on the gaseous pollutant transport and the source identification, its influence is analyzed theoretically and a conclusion is drawn that the velocity of fluid is a key factor to effectively help weaken the gravitational influence. Further studies for a given 2-D case by using the computational fluid dynamics （CFD） method show that when the velocity of inlet is less than one certain value, the influence of gravity on the pollutant transport is very significant, which will change the velocity field obviously. In order to quantitatively judge the practical applicability of identification approach, a synergy degree of the velocity fields before and after a source appearing is proposed as a condition for considering the influence of gravity. An experimental device simulating pollutant transmission was set up and some experiments were conducted to verify the practical application of the above studies in the actual gravitational environment. The results show that the proposed approach can successfully locate the sudden constant source when the experimental situations meet the identified conditions.

关键词： Experiment Gaseous pollutant source identification Gravitational field Location probability Synergy degree of velocity fields Ventilated enclosed space

Molecular mechanisms for interaction of glycine betaine with supra-molecular phycobiliprotein complexes

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Science China Chemistry 2009年第11期52卷 1865-1870页

作者： XU XiuLing LI Heng XIE Jie zhao jingquan Beijing National Laboratory for Molecular Sciences(BNLMS) Photochemistry LaboratoryInstitute of ChemistryChinese Academy of SciencesBeijing 100190China

Glycine betaine(GB) is a biologically important small molecule protecting cells,proteins and enzymes in vivo and in vitro under environmental ***,it was found that GB could also relax the structure and inactivate the function of phycobiliproteins and phycobilisome(PBS),a kind of supramolecular complexes,in cyanobacterial *** molecular mechanisms for the opposite phenomena are quite *** PBS and a trimeric or monomeric C-phycocyanin(C-PC) as models,the molecular mechanism for the interaction of GB with supra-molecular complexes or nuclear proteins was *** energetic decoupling of PBS components induced by GB suggests that the PBS core-membrane linking polypeptide was the most sensitive site while the rod-core linker was the *** analysis proves that PBS structure was loosened but not dissociated into the *** the basis of the results and structure knowledge,it was proposed that GB screened the electrostatic attraction of the opposite charges on a linker and a protein leading to a much looser *** was observed that GB induced a spectral blue shift for trimeric C-PC but a red shift for a monomeric C-PC(a nuclear protein),which were ascribed to GB's screening of the electrostatic attraction of a linker to a protein and strengthening of the hydrophobic interaction between C-PC *** trimers and monomers' forming of the same products under high concentration of GB was ascribed to a compromise of the opposite interaction forces.

关键词： glycine betaine phycobiliproteins phycobilisome supra-molecular complex molecular interaction mechanism

Flow Boiling of Ammonia in a Diamond-Made MicroChannel Heat Sink for High Heat Flux Hotspots

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Journal of Thermal Science 2020年第5期29卷 1333-1344页

作者： YANG Qi MIAO Jianyin zhao jingquan HUANG Yanpei FU Weichun SHEN Xiaobin School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Beijing Key Laboratory of Space Thermal Control Technology Beijing Institute of Spacecraft System EngineeringChina Academy of Space TechnologyBeijing 100094China

To solve the heat dissipation problem of electronic devices with high heat flux hotspots,a diamond microchannel heat sink consisting of 37 parallel triangular microchannels with channel lengths of 45 mm and hydraulic diameters of 280|im was *** flow boiling heat transfer characteristics of ammonia in the microchannels were investigated under high heat fluxes of 473.9-1000.4 W/cm^*** flow boiling experiments with saturation temperatures of 25℃,30℃,and 35℃ and mass fluxes of 98-1200 kg/m^2s were conducted,as well as subcooled flow boiling with inlet subcooling of 5℃ as a *** temperature and pressure drop measurements were *** main conclusions below can be drawn.(1)At a given heat flux,the heat source temperature first decreased and then increased with the mass flux,and there existed an optimum mass flux to optimize the cooling performance of the heat sink.(2)The heat transfer performance under the saturated inlet condition was obviously better than that under the subcooled inlet condition.(3)A larger saturation temperature leaded to weakening of both the heat transfer capacity and the stability of the microchannel heat ***,with the high heat diffusion ability of the diamond substrate and the great heat transfer capacity of ammonia flow boiling in microchannels,the heat sink can achieve a heat removal capacity of up to 1000.4 W/cm^2.

关键词： high heat flux flow boiling microchannel ammonia multipoint heat sources

Hydrogen ions directly regulating the oligomerization state of Photosystem I in intact Spirulina platensis cells

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Chinese Science Bulletin 2008年第2期53卷 317-320页

作者： ZHANG Rui XIE Jie HU ChangChao zhao jingquan Beijing National Laboratory for Molecular Sciences (BNLMS) and Key Laboratory of Photochemistry of CAS Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

H+ concentration induced-monomerization or trimerization of photosystem I (PSI) in cyanobacteria has never been directly observed. In this work, taking characteristic spectra for the trimers and monomers as the indicators, it was experimentally demonstrated that H+ could induce the oligomeric changes of PSI reaction centers in the intact Spirulina platensis cells and also in the isolated thylakoid membrane complexes. Especially, the higher concentration of H+ would induce the monomerization while the lower the trimerization, suggesting the electrostatic interaction should be mainly responsible for changes in the oligomeric state of PSI in Spirulina platensis.

关键词：光合体系三聚作用氢离子植物细胞低聚反应

New mechanism revealed for light-state transition in cyanobacterium Arthrospira platensis according to 77-K fluorescence kinetics

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Chinese Science Bulletin 2012年第11期57卷 1261-1265页

作者： XU XiuLing ZHANG Rui XIE Jie zhao jingquan Beijing National Laboratory for Molecular Sciences Key Laboratory of PhotochemistryInstitute of ChemistryChinese Academy ofSciencesBeijing 100190China

The mechanisms of oxygen evolution and carbon fixation in oxygenic organisms depend on the equal distribution of excitation energy to photosystems Ⅰ and Ⅱ, which is regulated by a mechanism referred to as light-state transition. In this work, a novel mechanism, energy spillover from PS Ⅰ to PS Ⅱ referred to as "inverse spillover", was revealed besides "mobile phycobilisome (PBS)" and the "spillover" of energy from PS Ⅱ to PS Ⅰ in cyanobacteria. Under continuous illumination with blue light, time-dependent 77-K fluorescence spectra demonstrated heterogeneous kinetics for the PBS and photosystem components, indicating that inverse spillover and mobile PBS work successively to regulate the excitation to a balanced distribution in cyanobacterial cells under blue light. Inverse spillover and mobile PBS occur under both 100 and 300 μmol m-2 s-1 blue-light conditions but they are accelerated under the latter.

关键词：荧光动力学过渡机制状态蓝藻螺旋藻均衡分配时间依赖性 PBS