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Luminescence resonance energy transfer based on β-NaYF_4:Yb,Er nanoparticles and TRITC dye

Science china chemistry 2009年第10期52卷 1590-1595页

作者： SUN LingDong, GU JianQin, ZHANG ShuZhuo, ZHANG YaWen & YAN ChunHua beijing National Laboratory for molecular Sciences, State Key Lab of Rare Earth Materials {2. and Applications & PKU-HKU Joint Lab in Rare Earth Materials and Bioinorganic {2., college of chemistry and molecular engineering, peking university, beijing 100871, china 1. beijing National Laboratory for molecular Sciences State Key Lab of Rare Earth Materials Chemistry and Applications & PKU-HKU Joint Lab in Rare Earth Materials and Bioinorganic Chemistry College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

β-NaYF4:Yb,Er nanoparticles (NPs) are one of the most efficient upconversion materials, which can convert near-infrared light to higher-energy light through multiple photon absorptions or energy transfer. In addition, they may be attractive alternative donors for luminescence resonance energy transfer (LRET) studies, because of their sharp absorption and emission profiles, high quantum yields, large anti-stokes shifts, long lifetime, low toxicity, and superior photo-stability. In principle, many problems of fluorescence resonance energy transfer (FRET), such as excitation of acceptors, emission overlaps between donors and acceptors, high background noise, potential toxicity, and instability, can be overcome using β-NaYF4:Yb,Er NPs as energy donors. Because the organic coating induced separation can significantly reduce the energy transfer efficiency and aqueous FRET system is difficult to be applied in devices, we demonstrate a novel NP-dye LRET system in solid state. The emission of the β-NaYF4:Yb,Er NPs at 539 nm overlaps with the absorption of the tetrametrylrhodarnine isothiocyante (TRITC), satisfying the requirement of LRET process. Since TRITC molecules are adsorbed on the β-NaYF4:Yb,Er NPs by an electrostatic interaction, the interaction distance is suitable for LRET without any further modulation. The resultant solid LRET system is ready for the further applications for devices.

关键词： upconversion emission β-NaYF4:Yb Er nanoparticles TRITC assembly luminescence resonance energy transfer (LRET)

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Approach to synthesis of novel chiral 3-chloro-2.5H)- furanone and its application in asymmetric reactions

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Chinese Science Bulletin 2000年第8期45卷 711-716页

作者： HUANG Hui & CHEN Qinghua1. Department of chemistry, Tonghua Teacher’s {2., Tonghua 134002. china 2. Department of chemistry, beijing Normal university, beijing 100875, china Department of chemistry Tonghua Teacher’s College Tonghua China Department of chemistry Beijing Normal University Beijing China

The synthetic method of the novel chiral synthon, 5-/-menthyloxy-3-chloro-2.(5H)-furanone 5a and its application in asymmetric reactions were investigated. 5a is easily obtained in highly optical purity, and acts as a stable acceptor of Michael addition with oxygen nucleophiles in tandem double Michael addition / internal nucieophilic substitution to offer the spiro-cyclopropane derivative containing four stereogenic centers 8, which it is difficult to obtain by routine methods. The synthetic methods for 5a and 8 are reported in detail and the new compounds are identified on the basis of their analytical data and spectroscopic data, such as UV, IR, H NMR,13 C NMR, MS and elementary analysis. The absolute configuration of the interesting spiro-cyclopropanes, spiro [1-chloro-4-(/-menthyloxy)-5-oxo-6-oxa-biscyclo[3.1.0]hexane-2.3i(4’-/-menthyloxy-5’-/-menthyloxy- butyrolactone)] 8 was established by X-ray crystallography. This result can provide important synthetic strategy in synthesis of some complex

关键词： new chiral synthon. 5-l-menthyloxy-3-chloro-2.(5H)-furanone absolute configuration spiro-cyclopropane derivative containing multiple chiral centers.

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TARTARIC ACID TEMPLATED SYNTHESIS OF MESOPOROUS Ti-INCORPORATED SILICA AND ITS CATALYTIC ACTIVITY FOR THE RING-OPENING POLYMERIZATION OF ε-CAPROLACTONE

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Chinese Journal of Polymer Science 2002年第4期20卷 361-368页

作者： Jie-bin Pang Chang-ming Dong Kun-yuan Qiu Yen Wei Department of Polymer Science and engineering {2. peking university beijing 100871, china Department of chemistry Drexel university Philadelphia, Pennsylvania 19104, USA peking Univ Coll Chem & Mol Engn Dept Polymer Sci & Engn Beijing 100871 Peoples R China Drexel Univ Dept Chem Philadelphia PA 19104 USA

Ti-incorporated mesoporous silica materials with pore diameters of 3-4 nm have been prepared via the co-hydrolysis and co-condensation reactions, that is the sol-gel reactions, of titanium (IV) tetrabutoxide and tetraethylorthosilicate in the presence of tartaric acid as template, followed by extraction with ethanol to remove the templatemolecules. The materials were characterized in detail by Fourier transform infrared spectroscopy, nitrogen adsorption-desorption test, powder X-ray diffraction, transmission electron microscopy and X-ray energy dispersive spectroscopy. Theresults indicate that the Ti-containing silica materials have large specific surface areas (ca. 12.0 m^2.g^(-1)) and pore volumes(ca. 0.900 cm^3 g^(-1)). The mesoporosity arises from disordered interconnecting channels or pores. The Ti-incorporated silicasexhibit catalytic activity for the ring-opening polymerization of ε-caprolactone, otherwise, the pure mesoporous silicamaterial shows no catalytic activity under the identical conditions.

关键词： Mesoporous material Ti-incorporated silica ε-Caprolactone Ring-opening polymerization Sol-gel reactions

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Synthesis and thermodynamic analysis of nano-La2.3

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Progress in Natural Science:Materials International 2007年第7期17卷 838-844页

作者： Liu Lili~(1,2. Tang Jie~2.Li Yuxiang~1 Zhang Mei~(1**) Wang Xidong~(1,3) (1.Department of Physical chemistry,{2. of Science and Technology beijing,beijing 100083,china 2.National Institute for Materials Science,Segen 1-2.1,Tsukuba 305-0047,Japan 3.college of engineering,beijing {2.,beijing 100871,china) [a]Department of Physical chemistry University of Science and Technology Beijing Beijing China [b]National Institute Materials Science Tsukuba Jpan [c]college of engineering Beijing University Beijing China

The thermodynamic parameters of La（NO3）3and La（OH）3are evaluated and the thermodynamics of nano-La2.3syn- thetic process is *** the base of thermodynamic analysis,La2.3nano-powders are prepared by the sol-gel method and the experi- ment scheme is designed by an orthogonal *** dry-gelatin is analyzed with differential thermal analysis/thermo-gravimetric analy- sis（TGA-DTA）and X-ray diffraction *** microstructure of nano-La2.3powders is observed by transmission dectron micro- *** synthetic parameters affecting the average grain size and dispersivity of nano-La2.3particles are experimentally examined and *** the results indicate that nano-La2.3particles well-dispersed are obtained and the average grain size is in the range of 2.—50 nm.

关键词： nano-La2.3 sol-gel thermodynamic analysis

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Investigation of 'chazi'(damaged-enamels)on Chenghua doucai Porcelains

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Science china(Technological Sciences) 2009年第6期52卷 1722-1729页

作者： DU Feng1 & SU BaoRu2.1 Institute of chemistry & molecular {2.,Qingdao university of Science & Technology,Qingdao,china 2.college of Information Science & Technology,Qingdao university of Science & Technology,Qingdao,china Institute of chemistry & molecular {2. Qingdao University of Science & Technology Qingdao China college of Information Science & Technology Qingdao University of Science & Technology Qingdao China

At the end of the 1950s,Sun Yingzhou considered that the 'chazi'(damaged colour)on Chenghua doucai imperial porcelain as a defect was originally produced in firing process during Chenghua period(1465―1487).Researchers in china have accepted his *** any fragment with the 'chazi' has never been found in several tons of Chenghua imperial sherds excavated from Ming imperial kiln site in *** china,few scholars have questioned the formation of 'chazi',and further investigated *** researchers at the Research Laboratory in the British Museum,employing unde-structive EDXRF,have analyzed the chemical composition of the 'chazi'(damaged colour)on a Chen-ghua doucai stem cup in the museum,and they have confirmed that the 'chazi'(damaged colour)was caused by the fire of the Jianfu palace in the Forbidden City in *** on their research,the authors studied the colour chemical principle of the 'chazi's' formation *** to the ceramic technology principle,scientific reasoning for the 'chazi' was carried *** the help of the history of Qing court,the brainteaser of the 'chazi' was totally uncovered,the misunderstanding for the 'chazi' has also been *** research also suggests that employing modern science and technology is a direction to study Chinese ancient ceramic further.

关键词： Chenghua doucai porcelains court eunuchs the set on fire at the Jianfu palace ’chazi’(damaged-enamels) the British Museum colour chemical principle archaeology using science and technology

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Pattern phenomena in an rf discharge dusty plasma system

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Science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 588-596页

作者： HUANG Feng1,2. YE Maofu2.& WANG Long2.1. college of Science, china Agricultural {2., beijing 100083, china 2. Institute of Physics, Chinese Academy of Sciences, beijing 100080, china 1. college of Science China Agricultural University Beijing 100083 China 2. Institute of Physics Chinese Academy of Sciences Beijing 100080 China

Various dust patterns are observed in an rf discharge dusty plasma system. According to the dust growth process from small to large in size, the formation of different dust patterns can be divided into two stages: the small-particle stage (or dust cloud stage), and the large-particle stage (or dust crystal stage). The evolution relations between different dust patterns with gas pressure changing are investigated. Dust voids, dust acoustic waves and strong turbulence modes are presented at the small-particle stage. The self-organized dust lattices and dust clusters are investigated at the large-particle stage. The static structure of a dust lattice is characterized by means of the pair correlation function. Dust clusters formed by particles with different numbers and the regular evolution of the clusters with gas pressure are also investigated. The packing sequences of dust clusters are verified through two-dimensional confined molecular dynamics simulations.

关键词： dusty plasma dust patterns

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Crystal Structure of 1,1-Dichloro-4-formyl-3-methyl-1a-phenyl-1a,2.3,4-tetrahydro-1H-azirino〔1,2.a〕〔1,5〕benzodiazepine(C18H16Cl2.2.)

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Chinese Journal of Structural chemistry 1999年第4期 31-34页

作者： XU JiaXi\ ZHANG XinYu\ JIN Sheng (college of chemistry and molecular engineering, peking university, {2.)

１ＩＮＴＲＯＤＵＣＴＩＯＮＢｅｎｚｏｈｅｔｅｒｏａｚｅｐｉｎｅｃｏｍｐｏｕｎｄｓａｒｅｉｍｐｏｒｔａｎｔｐｈａｒｍａｃｅｕｔｉｃａｌａｇｅｎｔｓ〔１，２〕．Ｉｎｒｅｃｅｎｔｙｅａｒｓ，ｉｔｈａｓｂｅｅｎｆｏｕｎｄｔ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＢｅｎｚｏｈｅｔｅｒｏａｚｅｐｉｎｅｃｏｍｐｏｕｎｄｓａｒｅｉｍｐｏｒｔａｎｔｐｈａｒｍａｃｅｕｔｉｃａｌａｇｅｎｔｓ〔１，２〕．Ｉｎｒｅｃｅｎｔｙｅａｒｓ，ｉｔｈａｓｂｅｅｎｆｏｕｎｄｔｈａｔｂｅｎｚｏｈｅｔｅｒｏａｚｅ...

关键词： crystal structure azirino1 2.1 5benzodiazepine 1

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SMALL ANGLE LIGHT SCATTERING MEASUREMENT OF THE ISOTROPIC TO NEMATIC TRANSITION OF A SIDE CHAIN NEMATIC POLYMETHACRYLATE

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Chinese Journal of Polymer Science 2002年第5期20卷 431-437页

作者： Zhong-ming Hu Ren-yuan Qian Shou-xi Chen Xiao-fang Chen Qi-feng Zhou Centre for molecular Science, Institute of chemistry Chinese Academy of Sciences, {2. 100080, china Department of Polymer Science & engineering college of chemistry & molecular engineering peking university beijing 100871, china Chinese Acad Sci Inst Chem Ctr Mol Sci Beijing 100080 Peoples R China peking Univ Coll Chem & Mol Engn Dept Polymer Sci & Engn Beijing 100871 Peoples R China

The kinetics of I-->N transition of a side chain nematic polymethacrylate has been studied by small angle depolarized light scattering intensity measurements using a charge coupled device linear image sensor. The polymer shows the transition temperatures K52.79I in degreesC, The H-v scattering intensity T(q,t) during the transition I (at 80.2.egreesC)-->N (at 75.8degreesC) shows that T(q) is independent of q for all t, and during the initial stage (in 6 s) T(t) increases exponentially with t. In the later stage of the transition T(t) approaches a saturation value in 2.min. This experimental result indicates that the I-->N transition of a liquid crystalline polymer is a spinodal type of phase transition mediated by orientation fluctuation.

关键词： side chain nematic polymer isotropic-nematic transition small angle depolarized light scattering

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Formation of nanotubes and secondary assemblies of cyclodextrins induced by BBOT

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Science china chemistry 2010年第9期53卷 2019-2025页

作者： ZHANG JingJing,SHEN XingHai,WU AiHua,ZHANG ChunFen,CHEN QingDe & GAO HongCheng beijing National Laboratory for molecular Sciences Radio{2. and Radiation {2. Key Laboratory of Fundamental Science college of chemistry and molecular engineering,peking university,beijing 100871,china 1. beijing National Laboratory for molecular Sciences Radiochemistry and Radiation chemistry Key Laboratory of Fundamental Science college of chemistry and molecular engineering Peking University Beijing 100871 China

The study of cyclodextrin nanotubes is a significant topic among the self-assembly behaviors of *** report herein the interaction of 2.5-bis(5'-tert-butyl-2.benzoxazoyl)thiophene(BBOT) with α-,β-,γ-cyclodextrins(CDs).It has been discovered that the reaction patterns of BBOT with CDs are remarkably different.α-CD forms a simple inclusion complex with BBOT in a stoichiometry of 1:2.guest:host).β-CD forms a 1:1 inclusion complex with BBOT at its low *** higher concentration of BBOT,the nanotube and secondary assembly of β-CD are *** for γ-CD,the nanotube and secondary assembly are formed within the whole concentration range of BBOT *** structure of γ-CD nanotubes is different from that of β-CD nanotubes to a certain extent.

关键词： BBOT cyclodextrin nanotube secondary assembly

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Measurement of Monomer Reactivity Ratios of D,L-3-Methylglycolide with Glycolide or D,L-Lactide

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Chinese Chemical Letters 2000年第9期11卷 815-818页

作者： Chang Ming DONG Kun Yuan QIU Zhong Wei GU Xin De FENG Department of Polymer Science and engineering, {2., peking university, beijing 100871 National Research Institute for Family Planning, beijing 100081 peking Univ Coll Chem & Mol Engn Dept Polymer Sci & Engn Beijing 100871 Peoples R China Natl Res Inst Family Plannning Beijing 100081 Peoples R China

For monomer reactivity ratios study, the copolymerization of D,L-3-methylglycolide (MG) with glycolide (GA) or D,L-lactide (LA) was carried out in bulk to a certain low conversion in the presence of stannous octoate at 140 degrees C. The copolymer compositions were determined by H-1 NMR spectroscopy. The monomer reactivity ratios were evaluated by Fineman-Ross method, Kelen-Tudos method and linear least-squares method. The monomer reactivity ratios of D,L-3-methylglycolide and glycolide or D,L-lactide are r(mg)= 0.73, r(ga)= 1.47; r(mg)= 1.71, r(la)= 0.92. respectively.

关键词： D,L-3-methylglycolide glycolide D,L-lactide ring-opening copolymerization monomer reactivity ratios

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