检索结果-南通市图书馆

Utilization of a spiropyran derivative in a polymeric film optode for selective fluorescent sensing of zinc ion

在线全文

学校读者我要写书评

暂无评论

science China chemistry 2006年第3期49卷 246-255页

作者： ZHANG Ying1, SHAO Na1, YANG Ronghua1, LI Ke’an1, LIU feng1, CHAN Winghong2 & MO Tian2 1. college of chemistry and Molecular {3., peking university, beijing 100871, China 2. department of chemistry, Hong Kong Baptist university, Hong Kong, China 1. college of chemistry and Molecular engineering Peking University Beijing 100871 China 2. department of chemistry Hong Kong Baptist University Hong Kong China

A new spiropyran derivative was synthesized and first utilized in a polymericfilm-based optical sensor for zinc ion. Spiropyrans, combining the characteristics of metal bindingand signal transduction, show potential function in the design of optical chemical sensors(optodes) toward metal ions. When embedded in a plasticized poly (vinyl chloride) (PVC) membrane,the newly synthesized spiropyran derivative 1 exhibits obvious fluorescence enhancement at 63. nm inthe presence of zinc ion in aqueous solution. With the optimum condition described, the optodemembrane responds to zinc ion over a dynamic range of 4.94x10^(-7) to 4.15x10^(-4)mol·L^(-1), witha detection limit of 1.51x10^(-7) mol·L^(-1). The membrane not only displays excellentphotostability, reproducibility and reversibility, but also exhibits high selectivity toward zincion over transition metal ions including Hg^(2+), Cd^(2+), Pb^(2+), Cu^(2+), Fe^(3.) and commoncationic ions presented in the physiological fluids.

关键词： spiropyran, sensor, PVC membrane, zinc ion, fluorescent spectroscopy.

A strategy for synthesis of polymer-protective bimetallic colloids

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of chemistry 1994年第1期12卷 11-18页

作者： WANG, Yuan GUI, Lin-Lin TANG, You-qidepartment of chemistry, {3. university, beijing 100871, China Institute of chemistry,Chinese Academy of sciences,beijing 100080 department of chemistry Peking University Beijing 100871 China

A strategy for the synthesis of polymer-protective bimetallic sols is proposed which has the advantage of the strong protective effect of the polymer agent on one of the composites to stabilize the bimetallic colloidal particles. This strategy is certified to be useful to the predication of the formation of stable bimetallic colloids protected by polymer and to the control of the particle size to a certain extent. A series of new PVP-protective bimetallic colloidal dispersions containing noble metal element (Pt, Rh, Pd), light transition metal element (Co, Fe), and boron are obtained from the corresponding salts by the methods of reduction by stage and coreduction, using the NaBH4 as reductant. The TEM, XRD and EPMA measurements indicate the formation of bimetallic colloids. An interesting kind of coil aggregation is observed in the systems of PVP-Pt-Co and PVP-Rh-Co prepared by the method of reduction by stage.

关键词： polymer-protective bimetallic colloids coil aggregation.

The synthesis and structural studies of mixed ligand complex,tris(1-phenyl-3.methyl-4-trifluoroacetylpyrazol-5-one)mono(1-phenyl-3.methyl-pyrazol5-one)neodymium(Ⅲ)monohydrate

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of chemistry 1990年第1期8卷 29-36页

作者： HUANG,Chun-Hui ZHANG,Shi-Wei DENG,An-Ping TANG,Hui-Tong XU,Guang-Xian department of chemistry,peking {3.,beijing 100871 department of chemistry Peking University Beijing 100871

A mixed ligand neodymium complex containing 1-phenyl-3.methyl-4-trifluoroacetyl- pyrazol-5-one(HPMTFP)and 1-phenyl-3.methyl-pyrazol-5-one(PMP),with molecular formula Nd(PMTFP)_3.PMP·H_2O was *** crystal and molecular structure has been determined by single crystal X-ray diffraction *** complex crystallizes in monoclinic system with space group C_2~5h-P2_(1/n).There are four formula units in a cell of dimensions a=12.83.(3.,b=23.763.5),c=16.810(4) ,β=109.58(2)°.The structure has been refined by full-matrix least-squares techniques to a final R value of 0.0487 and Rw value of *** neodymium atom is coordinated to eight oxygen atoms with the average Nd-O bond length 2.43.,Its thermostability,and mass spectrum have been discussed.

关键词： phenyl-3.methyl-4-trifluoroacetylpyrazol-5-one)mono phenyl-3.methyl-pyrazol5-one)neodymium monohydrate The synthesis and structural studies of mixed ligand complex,tris

VOLTAMMETRIC BEHAVIORS OF ADRENALINE AND ITS Be(Ⅱ)COMPLEX

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1991年第9期2卷 731-734页

作者： Xian Zeng YE Jian Min HOU Song GAO Xiao Xia GAO department of chemistry,peking {3.,beijing 100871 De Min WANG department of Technical Physics,peking {3.,beijing 100871

The electrochemical oxidation behaviors of adrenaline(AD)and its Be(Ⅱ)complex have been studied by voltammetric method with a carbon paste working *** the bases of calculation of the atomic net electronic charges of AD molecule by INDO approximate method and results of comparative experiment with dopamine the possible coordination site of Be(Ⅱ)-AD complex is proposed.

关键词： VOLTAMMETRIC BEHAVIORS OF ADRENALINE AND ITS Be COMPLEX AD ITS

GRAFT COpolymerIZATION OF ACRYLAMIDE ONTO POLY（N-PARA-TOLYLACRYLAMIDE） FILMS INITIATED BY CERIC ION

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of polymer science 1988年第1期6卷 75-83页

作者：丘坤元宋叶 department of chemistry peking university beijing

Functional monomers having phenylcarbamoyl and p-tolylcarbamoyl were synthesized. Binary initiation system consisted of Ce4+ and these functional monomers could initiate acrylamide polymerization. It was found that acrylamide could graft copolymerize onto macromolecules having these functional monomers units. The formation of graft copolymer has been verified by its percentage of water absorption, contact angle with water, XPS and SEM photographs. The reaction mechanism was proposed and the main reactive site of graft ocpolymerization initiated by Ce4+ would take place predominantly at the functional pendant group.

关键词： Acrylamide Functional monomers N-para-tolylacrylamide Copolymers Graft copolymerization initiated by ceric ion Characterization of grafted copolymers by SEM XPS.

New color centers and luminescence of BaFI: Eu2+

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

science Bulletin 1997年第15期42卷 1268-1271页

作者： CHEN Wei and SU Mianzeng1. Laboratory of Semiconductor Materials sciences, Institute of Semiconductor, Chinese Academy of sciences, beijing 100083. China 2. {3. of chemistry, peking university, beijing 100871, China Laboratory of Semiconductor Materials sciences Institute of Semiconductor Chinese Academy of Sciences Beijing China department of chemistry Peking University Beijing China

MANY publications have appeared on the photostimulated luminescence (PSL) of alkalineearth mixhalides. Color centers play a very important role in the PSL and X-ray storage imag-ing processes. The F centers, V centers and oxygen-related centers in this kind ofcrystals have been investigated. All these reports provide some useful information to the PSLmechanism and thus improve the practical applications of these materials. New color centers in

关键词： BaFI:Eu2+ color centers photostimulated luminescence.

SYNTHESIS OF NOVEL SOLUBLE AROMATIC POLYPYROMELLITIMIDE CONTAINING ORDERED 1,2,4-TRIAZINE IN THE MAIN CHAIN

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of polymer science 2002年第3期20卷 219-224页

作者： Xiao-bing Yi Guo-shi Wu feng-cai Lu department of chemistry Tsinghua {3., beijing 100084 China Institute of chemistry Chinese Academy of sciences, beijing 100080, China Tsing Hua Univ Dept Chem Beijing 100084 Peoples R China Chinese Acad Sci Inst Chem Beijing 100080 Peoples R China

A new heat-resistant, soluble polymer, poly(phenyl-1,2,4-triazine imide), has been prepared via a two-step method of polycondensation of N,N'-bis(4-benzil)pyromellitimide and terephthalamidrazone in cresol, followed by curing at higher temperature. The rigid 1,2,4-triazine group increases the solubility of the polyimide so that the polymer is soluble in cresol, N-methyl-2-pyrrolidone (NMP), trifluoroacetic acid and concentrated sulfuric acid, etc. Thermogravimetric analysis (TGA) indicates that this novel polyimide has good thermal stability with a high decomposition temperature of 447degreesC in air and of 423.degreesC in N-2, It has a tensile strength of 107.4 MI'a with an elongation at break of around 7.6%.

关键词： polyimides N,N '-bis(4-benzil)pyromellitimide rigid-rod group 1,2,4-triazine

Synthesis and X-ray crystal structure of oxamido-bridged heterobinuclear Ni(Ⅱ)-Cu(Ⅱ) complexes

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of chemistry 1994年第6期12卷 503-508页

作者： WEI, Ping-Rong JIA, Lu LIU, Chang-Rang FAN, Yao-Tingdepartment of chemistry, Zhengzhou university, Zhengzhou, Henan 450052, ChinaGAO, SongResearch Center of Rare Earth chemistry, peking university, beijing 100871, China 1department of chemistry Zhengzhou University Zhengzhou Henan 450052 China2Research Center of Rare Earth Chemistry Peking University Beijing 100871 China

The two complexes [Ni(oxen)Cu(L)2](ClO4)***2O (L=2,2'-bipyridyl(bpy), 1,10-phenanthroline(phen)) have been synthesized, where oxen is N,N'-bis(2-aminoethyl)oxamido di-anion. The crystal structure of [Ni(oxen)Cu(bpy)2](ClO4)***3.H has been determined by X-ray diffraction method. The crystal is triclinic system, space group P1 with a=12.179(1),b=12.298(2), c=11.476(2) A, a=97.57(1), B=97.52(1), 7=80.29(2), V=1669.04(67) A3. Z=2, Dcalcd=1.667 g/cm3. The structure has been refined to final R of 0.076 and Rw of 0.080, respectively. The complexes have an extended oxamido-bridged structure and consist of Ni(Ⅱ) ion in a square planar environment and Cu(Ⅱ) ion in a distorted octahedral environment.

关键词： N,N'-bis(2-aminoethyl)oxamidonickel(II) heterobinuclear complexes crystal structure.

STUDY ON POLYSULFONE-POLYESTER BLOCK COpolymerS

在线全文

学校读者我要写书评

暂无评论

高分子科学(英文版) 1988年第4期6卷 314-324页

作者：丁有骏齐大全 department of chemistry peking university peking university beijing beijing

Synthesis and characterization of a series of Polysulfone (PSF)-Polyester (PEs) block copolymers were *** degree of randomness (B) of these block eopolymers was calculated from the intensities of their proton signals in ~1H NMR spectra and lies in the region of 0polymers were relatively dependent on the reaction conditions, various feed ratios and structure of *** phenomenon was observed, when the PSF-PEs block copolymers dissolved in different solvents they had different viscosities and molecular *** PSF-PEs block copolymers had better solvent resistance than homo-polysulfone.

关键词： Polysulfone-polyester block copolymer Degree of randomness, sequential structure of copolymer