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Wavelet fractal character of overlapping signal

Chinese Science Bulletin 2003年第1期48卷 44-49页

作者： QIU Jianding1,2. ZOU Xiaoyong1, LIANG Ruping1,2. mo jinyuan1 & CAI Peixiang1 1. School of Chemistry and chemical {2., Zhongshan Univer-sity, Guangzhou 5102.5, china 2. Department of chemical {2., pingxiang college, pingxiang 337055, china correspondence should be addressed to mo jinyuan (e-mail: cesmjy @***) School of Chemistry and chemical engineering Zhongshan University Guangzhou 510275 China Department of chemical engineering Pingxiang College Pingxiang 337055 China

A new method based on the combining of the wavelet theory with the fractal theory and named wavelet fractal peak position method (WFPPM) is introduced to ex-tract the number of the components and the relevant peak positions from overlapping signals in chemistry. The over-lapping signal is first transformed into continuous wavelet transform value of time domain in certain dilation range via continuous wavelet transform (CWT), and then changed into capacity dimensions (Dc). The number of the components and the relevant positions of overlapping peaks can be iden-tified easily according to the change of Dc. An investigation concerning the influence of different dilation ranges on the peak positions extracted by WFPPM is also provided. Stud-ies show that the WFPPM is an efficient tool for extracting the peak positions and identifying the number of peaks from unresolved signals, even when this kind of overlapping is significantly serious. Relative errors of less than 1.0% in peak positions are found when WFPPM is used in the pro- cessing of the cadmium(Ⅱ)-indium(Ⅲ) mixture system. The analytical results demonstrate that the desired peak positions can be extracted conveniently, accurately and rapidly from an unresolved signal via WFPPM. Tremendous developing and applications based on currently reported WFPPM in extracting overlapping signals would be expected in the near future.

关键词：重叠信号化学信号电分析化学分离度小波伸缩尖峰位置

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Periodicity and map for discovery of new ionic liquids

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Science china Chemistry 2006年第2期49卷 103-115页

作者： ZHANG Suojiang, SUN Ning, ZHANG Xiangping & Lü Xingmei Research Laboratory for Green chemical engineering and Technology, Institute of Process engineering, Chinese Academy of Sciences, Beijing 100080, china correspondence should be addressed to Zhang Suojiang 1. Research Laboratory for Green chemical engineering and Technology Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 China

There is virtually no limit in the number of ionic liquids. How to select proper ones or discover new ones with desirable properties in such a large pool of ionic liquids? It has become a bottleneck in the researches and applications of ionic liquids. Mendeleev’s periodic law states that the properties of the elements vary periodically. Whether the similar regularity exists among ionic or mo-lecular fragments of compounds is an interesting topic. In this work, we attempted to establish a pe-riodicity and draw a “map” of ionic liquids for providing definite guidance to discover, design, and se-lect the proper ionic liquids rather than trial-and-error. If a complete regularity of the system of ionic liquids can be finally established in the future, we are near an epoch in understanding the existing differences and the reasons for the similarity of the ions or molecular fragments.

关键词： ionic liquids molecular fragment periodicity map

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Synthesis,crystal structure of a novel yttrium (Ⅲ) coordination compound supported by typical plenary Dawson cluster

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Chinese Science Bulletin 2003年第23期48卷 2585-2588页

作者： WANG Jingping, WEI Meilin & NIU Jingyang School of Chemistry and chemical engineering, Henan University, Kaifeng 475001, {2. correspondence should be addressed to Niu Jingyang (e-mail: jyniu@ ***) School of Chemistry and chemical engineering Henan University Kaifeng China

A novel yttrium (III) coordination compound supported by plenary Dawson cluster, [Y(NMP)5(H2.)2. [Y(NMP)4(H2.)2.P2.o18O62.] · NMP · 5.5 H2., (NMP = N-methyl-2.pyrrolidone) has been synthesized by reaction of α-H6P2.o18O62.· nH2., Y2.3 and NMP in water. The results of the single crystal X-ray diffraction analyses show the title compound forms a neutral and discrete cluster through [P2.o18O62.6−] being coordinated to [Y(NMP)4(H2.)2.3+ through its terminal oxygen atom.

关键词：晶体结构钇 X射线衍射分析氧原子

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Determination of Trace Silver( Ⅰ ) in Basic Aqueous Solution by Electrochemiluminescence of a New Reagent 6-(2.Hydroxy-4-Diethylaminophenylazo)-2.3-Dihydro-1,4-Phthalazine-1,4-Dione

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chemical Research in Chinese Universities 1991年第1期7卷 32-36页

作者： An Jingru Lin Jinming (Department of Chemistry, Fuzhou University, Fuzhou) To whom correspondence should be {2..

The electrochemiluminescence (ECL) of a new reagent 6- (2.hydroxy- 4 diethy laminophenylazo)-2.3-dihydro-1 ,4-phthalazine-1,4-dione (HDEA) in a basic aqueous so lution was studied by using the apparatus designed by ourselves. Trace amounts of silver ( Ⅰ ) shows a significant effect on the efficiency of light emission of HDEA during a positive trigonometrical wave pulse was exerted on the solution. The linear relationship between the light intensity and the concentration of silver( Ⅰ ) occurs in the range of 5. 0×10-8 to 3. 0×10-8 mol/L Ag(Ⅰ ) in a medium of KOH-KCl-HDEA (pH= 12. 8). The detection limit of the method is 2. 0×10-8 mol/LAg( Ⅰ ), and the r. s. d. for 1.0×10-7 mo)/L Ag ( Ⅰ ) is 5%. Of 2. metal ions concerned, only nickel( Ⅱ ), cerium( Ⅳ ) and cobalt( Ⅱ ) interfere the silver detection seriously; Ⅰ and Br also have some interference.

关键词： Electrochemiluminescence Reagent Silver 6 ( 2.Hydroxy-4 diethy laminophenylazo)-2.3-dihydro-1 4-phthalazine 1 ,4-dione

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PREPARATION AND CHARACTERIZATION OF K₁₃[Nd(Gew₉mo_{2./sub>O₃₉_{2./sub>]·2.H_2./sub>O}}

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Chinese chemical Letters 1994年第1期5卷 59-62页

作者： Qing Yin WU Sheng Xian XU and Yu Lin SONG (Department of Chemistry, Liaoning University, Shenyang, 110036)(Author to whom correspondence should be {2..)

The heteropoly comples K(13)[Nd (GeW9mo2.(39)2.·2.H2. has been prepared for the first time and characterized by chemical analysis, IR spectrum, UV spectrum, X-ray powder diffrection and thermal analysis.

关键词： Nd mo Gew9mo2.

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Novel pyrano[4,3-c][2.-benzopyran-1,6-dione derivative from medicinal fungus Phellinus igniarius

Novel pyrano[4,3-c][2]-benzopyran-1,6-dione derivative from ...

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The 3～(rd) International Conference on Natural Products :Natural Products -a Must for Human Survival ABSTRACTS

作者： Ying Wang, Shunyan mo, Jiangong Shi Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical college, Beijing 100050, People's Republic of china To whom {2. should be addressed.

Fungi produce an astonishing variety of structurally unusual secondary metabolites and seem to be an endless source of novel structures. Phellinus igniarius (DC. Ex Fr.) Quel, a fungus belonging to Polyporaceae family, preferably hosts on the stems of aspen, robur and birch. Its fruit body is used to treat fester, bellyache and bloody gonorrhea in traditional Chinese medicine. In our prior reports, the chemical components of the ethanol extract of the fruit body of Phellinus igniarius have been described, including phelligridins A-F and inoscavin A. The remaining portions of the extract showed strong antioxidant activity in the in vitro test. In our continual chemical investigation on these active portions, an unusual pyrano[4,3-c][2.-benzopyran-1,6-dione derivative named phelligridin G (4) were isolated and characterized, together with phelligridin C (1), D (2., F (3) and inoscavin A (5). The structure of phelligridin G (4) was elucidated as8,9-dihydroxy-3-{5',6'-dihydroxy-5''-(5''',6'''-dihydroxystyryl)-3''-oxo-spiro[fural-2.'(3''H),1'-indene] -2.-yl}-1H,6H-pyrano[4,3-c][2.benzopyran-1,6-dione by spectroscopic methods including IR, MS, 1D and 2. NMR experiments. The antioxidant activities of these compounds are in testing.

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