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Microwave assisted synthesis,spectroscopy and biochemical aspects of lanthanum(Ⅲ) and praseodymium(Ⅲ) complexes with oxadiazole functionalised dithiocarbazinates

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Journal of Rare Earths 2009年第5期27卷 698-704页

作者： Shweta Singh O P Pandey S K Sengupta department of chemistry D.D.U.Gorakhpur University chemistry department University of Surrey

The new lanthanum (Ⅲ) and praseodymium (Ⅲ) complexes of the general formula [Ln(L)3] (Ln=La(Ⅲ) or Pr(Ⅲ); LK=potassium salt of dithiocarbazinates) were prepared by both, conventional thermal and by the use of microwave technology. Elemental analyses, electrical conductance, magnetic moment and electronic, infrared, far-infrared, 1H and 13C NMR spectral studies were used to characterize the complexes. The molecular weights of few complexes were determined by FAB-mass spectra. Nephelauxetic ratio, covalency parameter and bonding parameter for these complexes were also calculated. The probable structures of the complexes were proposed. The antifungal and antibacterial activities of the complexes were evaluated. The activities were correlated with the structures of the compounds.

关键词： lanthanum (Ⅲ) praseodymium (Ⅲ) dithiocarbazinates microwave synthesis structures antifungal antibacterial rare earths

Synthesis,Characterization and Weak Intramolecular Interactions of Porphyrins Bearing Nucleobases

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Chinese Journal of chemistry 2003年第11期21卷 1451-1457页

作者：阮文娟李瑛赵小菁王传忠朱志昂缪方明 department of chemistry Nankai University department of chemistry Tianjin Normal University

5, 10, 15-Triphenyl-20-{2-[alpha-(adenine-9) acetylamino]} phenyl porphyrin (1), 5,10,15-triphenyl-20-{2-[alpha-(cytosine-]}acetylamino]} phenyl porphyrin (2), 5, 10, 15-triphenyl-20-{4-[alpha(cytosine-1)ethoxy]} I I phenyl porphyrin (3) and their zinc complexes Zn-1, Zn-2 and Zn-3 have been prepared and characterized by H-1 NMR spectra, elemental analyses, electronic absorption spectra and mass spectra (FAB). Intramolecular pi-pi interactions and intramolecular metal-pi interaction for 1, 2, Zn-1, and Zn-2 have been investigated by several methods. H-1 NMR studies demonstrate that the porphyrin pi-system in 1 and 2 is parallel to the adenine and the cytosine aromatic ring, respectively. The electronic absorption spectral properties of free porphyrin derivatives and their zinc complexes have been compared with those of H2TPP and ZnTPP. The results show that the UV-vis spectra of 1 and 2 are the same as that of H2TPP, whereas the spectra of their zinc complexes show 7 nm red shifts of the Soret bands compared to that of ZnTPP. The emission spectra of Zn-1 and Zn-2 are independent of excitation wavelength. From combination of the evidence of absorption and emission spectra it is suggested the existence of intramolecular metal-pi interaction in Zn-1 and Zn-2. The results of conformational analysis agreed quite nicely with that of experiments, thus it was further to validate the experimental conclusions.

关键词： porphyrin pi-pi interaction spectra conformational analysis

Plasmonic coupling in single flower-like gold nanoparticle assemblies

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Progress in Natural Science:Materials International 2016年第5期26卷 449-454页

作者： Yi Luo Lacie Dube Yadong Zhou Shengli Zou Jing Zhao department of chemistry University of Connecticut department of chemistry University of Central Florida

Localized surface plasmon resonance(LSPR) arises when light interacts with metallic nanoparticles(NPs).When nanoparticles(NPs) assemble together, the plasmon coupling effect between the NPs often leads to new features in the LSPR of the assembled structure. Understanding the plasmon coupling in the complex assemblies will greatly benefit the development of new plasmonic devices. Here we demonstrate the fabrication of a 3D structure using two different sized Au NPs as building blocks. This 3D structure was achieved by manipulating the binding efficiency of ligands linking the NPs, and proper choice of the NP size. The assembled structure is flower-like structure, with one 130 nm Au NP in the center, and several 40 nm Au NPs attaching as"petals". Single particle dark-field scattering measurements of the individual assemblies were performed,together with electrodynamics simulations. The experimental and theoretical studies show that, the plasmonic coupling lead to broadening of the LSPR and additional peaks, depending on the number and 3D arrangement of the 40 nm NPs around the center 130 nm NP.

关键词： Metal nanoparticle Assembly Plasmon Coupling Single particle

SYNTHESIS AND CHARACTERIZATION OF TRIAZOLE CONTAINING LIQUID CRYSTALLINE POLYMERS THROUGH 1,3-DIPOLAR CYCLOADDITION POLYMERIZATION

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Chinese Journal of Polymer Science 2009年第6期27卷 761-770页

作者： Devamani Srividhya Sundaram Manjunathan Sivashankaran Nithyanandan Subramanan Balamurugan Sengodan Senthil department of chemistry Sona College of Technology department of chemistry Anna University

Liquid crystalline polymers containing 1,2,3-triazole units as linking groups have been synthesized from the monomers containing triad ester diazide and flexible dialkyne ester by 1,3-cycloaddition reaction and were characterized. Click reaction of azide and alkyne functionals catalyzed by Cu(I) yielded target polyesters with 1,2,3-triazole *** structure of the polymer was confirmed by spectral *** analysis reveals that the polymers have moderate molecular weight with narrow distribution.H...

关键词： Triazole Click chemistry Main chain polymers Azide-alkyne cycloaddition Liquid crystalline polymers

Molecular Dynamics Studies of the Kinetics of Phase Changes in Clusters IV:Crystal Nucleation from Molten (NaCl)_(256) and (NaCl)_(500) Clusters

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Chinese Journal of chemistry 2003年第12期21卷 1543-1552页

作者：李小华黄锦凡 department of chemistry Nanjing Xiaozhuang College department of chemistry University of Michigan

Molecular dynamics computer simulation based on the Born-Mayer-Huggins potential function has been carried out to study the effects of cluster size and temperature on the nucleation rate of sodium chloride clusters in the temperature range of 580 K to 630 K. Clusters with 256 and 500 NaCl molecules have been studied and the results have been compared with those obtained from 108 molecule clusters. The melting point (MP) of the clusters were observed to increase with the size of the clusters and can be well described by a linear equation MP=1107(37)-1229(23)N -1/3 (N is the number of molecules in the cluster). The nucleation rate was found to decrease with increasing the cluster size or temperature. Various nucleation theories have been used to interpret the nucleation rates obtained from this molecular dynamics simulation. It is possible to use a constant diffuse interface thickness to interpret the nucleation rate from the diffuse interface theory in the temperature range of this study. However,the interfacial free energy estimated from classical nucleation theory and diffuse interface theory increases too fast with increasing the temperature while that from Gran-Gunton theory does not change with changing temperatures. The sizes of critical nuclei estimated from all the theories are smaller than those estimated from our simulations.

关键词： sodium chloride crystal nucleation rate interfacial free energy size dependence temperature dependence

PREPARATION AND SWELLING PROPERTIES OF SUPER-ABSORBENT POLYMER

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Chinese Journal of Polymer Science 1996年第1期14卷 48-56页

作者：柳明珠程镕时吴靖嘉 department of chemistry Nanjing University Nanjing 210093 department of chemistry Lanzhou University Lanzhou 730000

A super-absorbent polymer is prepared by graft polymerizing acrylamide (AM) onto potato starch using eerie ammonium nitrate (CAN) and N, N'-methylene-bis-acrylamide (bisAM) as an initiator and cross-linking agent respectively, and then subjecting the potato starch- poly(acrylamide) (PAM) graft copolymer (SPAM) to alkaline saponification. The water absorbency (WA) of the sample is nearly 5000 g H2O/g for dry sample in 24 h at room temperature and is far larger than that of reported in the literature([1]). The variables affecting the WA were investigated and optimiz;ed, they were: concentrations of potato starch, AM, CAN and bisAM were 26.3 g/L, 1.14 mol/L, 10.3 mmol/L and 0.53 mmol/L, respectively. The amount of sodium hydroxide was 15 g and the temperatures of graft copolymerization and saponification reactions were 60 degrees C and 95 degrees C. The time of graft copolymerization and saponification reactions was 2 h, respectively.

关键词： graft copolymer super-absorbent polymer potato starch acrylamide

Two Coordination Novel Polymers Based on a Flexible Ligand N,N'-diacetic Acid Imidazolium

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Chinese Journal of Structural chemistry 2017年第3期36卷 463-470页

作者：柴小川高晓娜李晖张汉辉韩秋萍 department of Applied chemistry Yuncheng University department of chemistry Fuzhou University

{[Cu_3（cis-DAM）_4（OH）_2]·12H_2O}_n 1 and [Ag_3（trans-DAM）_2（NO_3）]_n 2 with a flexible ligand N,NA-diacetic acid imidazolium（HDAM） were synthesized and characterized by single-crystal X-ray diffraction. Compound 1 crystallizes in the orthorhombic I222 space group with a = 12.033（2）,b = 12.498（3）,c = 14.963（3） A,V = 2250.4（8） A^3,Z = 8,C_7H_（13.5）N_2O_（7.5）Cu_（0.75）,M_r = 293.35,D_c = 1.732 g·cm^-3,F（000） = 1210,GOF = 1.087,the final R（I 〉 2σ（I）） = 0.0521 and w R（all data） = 0.1386. Compound 2 crystallizes in the monoclinic C2/c space group with a = 21.601（4）,b = 8.321（2）,c = 13.589（3） A,β = 126.95（3）°,V = 1951.9（7） A^3,Z = 8,C_7H_7N_（2.5）O_（5.5）Ag_（1.5）,M_r = 375.96,D_c = 2.559 g·cm^-3,F（000） = 1448,GOF = 1.017,R（I 〉 2σ（I）） = 0.0222 and w R（all data） = 0.0633. Compound 1 displays a novel 2D layer,consisting of a couple of left-helical chains with a pitch of 12.498（3） A formed by μ_3-cis-DAM~– ligands and Cu（1） ions,which are stabilized by hydrogen bonding interactions to give a 3D supramolecular framework. As for 2,Ag（1） ions are doubly bridged by trans-DAM~– and NO_3~– to form [Ag（1）_2O_4] chains,which are further connected by Ag（2） and trans-DAM~– to build a 3D framework. Additionally,thermogravimetric analyses,FT-IR spectroscopy,UV-visible spectroscopy,and the fluorescent properties were discussed.

关键词： N N'-diacetic acid imidazolium crystal structure helical chains fluorescent

Promotional effects of samarium on Co_3O_4 spinel for CO and CH_4 oxidation

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Journal of Rare Earths 2014年第2期32卷 159-169页

作者：徐香兰韩红刘建军刘文明李文龙王翔 Institute of Applied chemistry Department of ChemistryNanchang University

A series of CO3O4 spinel catalysts modified by Sm were prepared by co-precipitation method and tested for CH4 and CO oxidation. The addition of a small amount of Sm into Co3O4 led to an improvement in the catalytic activity for both reactions. Co0.98Sm0. 02 and Co0.95Sm0.05, the two samples with Co/Sm molar ratio of 0.98/0.02 and 0.95/0.05 in sequence, showed the similar and the highest activity for CH4 oxidation, with CH4 complete conversion at 450 ℃. In contrast, Coo.90Smo l0 was the most active sample for CO oxidation, with CO complete conversion at 120 ℃. The catalysts were characterized by techniques of N2 adsor- tion-desorption with Brunauer-Emmett-Teller technique （N2-BET）, X-ray powder diffraction （XRD）, thermal gravity analy- sis-differential scanning calorimetry （TGA-DSC）, Hz temperature programmed reduction （H2-TPR） and X-ray photoelectron spec- troscopy analysis （XPS）. Compared with pure Co3O4, for CO1-xSmx catalysts with 0.02≤x≤0.10, the addition of a small amount of Sm resulted in the formation of spinel Co3O4 and amorphous SmCoO3, hence increasing the number of Co3＋ and the active surface oxygen species, which was responsible for the improvement of the activity. C00.95Sm0.05 catalyst showed not only high thermal stability and activity but also good reaction durability in the presence of 5% water vapor for CH4 oxidation.

关键词： Co3O4 SmCoO3 CO and CH4 oxidation water vapor effect rare earths

POLYROTAXANE WITH π-CONJUGATED PORPHYRIN AND POLYAZOMETHINE SYSTEMS PREPARED FROM A TYPE OF PORPHYRIN-DIALDEHYDE AND COMPLEX OF β-CYCLODEXTRIN WITH 1,4-PHENYLENEDIAMINE

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Chinese Journal of Polymer Science 2013年第1期31卷 139-147页

作者： Raziyeh Akbarzadeh Hossein Dehghani department of Inorganic chemistry Faculty of ChemistryUniversity of Kashan

The synthesis of 5,15-bis[4-（methoxycarbonyl）phenyl]-10,20-diphenylporphyrin （2） and its reduction to 5,15- bis[4-（hydroxymethyl）phenyl]-10,20-diphenylporphyrin （3）, and so its oxidation to provide 5,15-bis（4-formylphenyl）-10,20- diphenylporphyrin （4） are reported. The copolymer possessing β-cyclodextrin （fl-CD）, n-conjugated porphyrin and polyazomethine systems was synthesized by the polycondensation of porphyrin-dialdehyde monomer （4） and ,β- cyclodextrin/1,4-phenylenediamine complex （5）. The monomers and the copolymer were characterized by UV-Vis, ^1H-NMR and IR spectra. Furthermore, ^1H-NMR and FT-IR spectra confirmed locating the aromatic ring of 1,4-phenylenediamine molecule in the center of β-cyclodextrin cavity.

关键词： Polymer Porphyrin 1,4-Phenylenediamine Imine Cyclodextrin.