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Conformational study of L-lysine in aqueous solution by lanthanide shift probes

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chinese Journal of Chemistry 1990年第5期8卷 423-429页

作者： ren,ji-min pei,{2.,wen-yun changchun institute of applied Chemistry,Academia Sinica,changchun 13002. changchun institute of {2. Chemistry Academia Sinica Changchun 130022

Conformation of L-lysine in aqueous solution was investigated by lanthanide shift probes (Dy,Ho,Er,Tm and Yb).Reilley's method was employed to separate the contact and dipolar com- ponents of the ^(13)C paramagnetic *** study reveals that C_α shift has the largest contact con- tribution while the other carbon shifts are dominated by the dipolar *** average overall conformation of L-lysine in aqueous solution is extended with the molecular backbone in trans form. In the complex,lanthanide ion coordinates to the carboxyl group with Ln—O bond length 2.2.(?)and the whole ligand is located outside the zero-dipolar shift cone of the lanthanide *** electronic spin density distribution on the ligand nuclei shows that the spin polarization is the predominant mech- anism of the contact interaction for nuclei in close proximity to the bound lanthanide ion.

关键词： than

~1H and ^(13)C NMR studies of TTHA complexes with diamagnetic rare earth ions

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chinese Journal of Chemistry 1995年第5期13卷 429-434页

作者： ZHANG, Shan-Rong ren, ji-min pei, {2.-kui LIU, Ai-Zhuo XIAO, Yan-wenapplied Spectroscopy Laboratory, changchun institute of applied Chemistry, chinese academy of sciences, changchun, jilin {12., China applied Spectroscopy Laboratory Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China

TTHA complexes with diamagnetic rare earth ions (La3+, Y3+ and Lu3+) were studied by 1H and 13C NMR spectroscopy. A symmetric structural model was suggested for La(TTHA) complex and an asymmetric model for Y(TTHA) and Lu(TTHA) complexes. The complex formation was dependent on the pH value of the solution. The interactions of La(TTHA) with the additional metal ions (La3+, Y3+ and Ca2.) were relatively weak, but relatively strong for that of Lu(TTHA) with the additional Lu3+.

关键词： NMR TTHA diamagnetic rare earth ions

STUDIES ON THE INTERFACIAL ADHESION BETWEEN FUNCTIONALIZED POLYPROPYLENE AND POLYAMIDE 1010

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chinese Journal of Polymer Science 1999年第3期17卷 237-244页

作者： Xiao-min Zhang Zhihui Yin Yongxian Song jinghua Yin Polymer Physics Laboratory, {2. institute of applied Chemistry, chinese academy of sciences, changchun 13002., China chinese Acad Sci Changchun Inst Appl Chem Polymer Phys Lab Changchun 130022 Peoples R China

The interface behavior of polyamide 1010 (PA1010) and polypropylene (PP) was studied. In order to improve their interfacial adhesion, functional PP was prepared by means of grafting glycidyl methacrylate (GMA) on PP main chains and used instead of plain PP. Several technological characterizations were performed here on their interfaces. ESCA was used to confirm that some kind of reaction occurred between end groups of PA1010 and epoxy species of PP-g-GMA. The peel test was adopted to measure interfacial adhesion. It was found that the fracture energy of interfaces between PA1010 and PP-g-GMA was dramatically increased with the content of GMA. Their interfaces were observed as being blurred by using SEM and TEM and a crack that could be seen in the case of the interfaces of the PA1010 and the plain PP disappeared.

关键词： polyamide 1010 polypropylene-g-GMA interface behavior adhesion

Syntheses of (C_5H_9C_5H_4)_2.nCl(THF)_n (Ln=Nd, Sm, Er, Yb) and crystal structure of [(C_5H_9C_5H_4)_2.LnCl(THF)_n]_2.Ln=Sm, n=1; Ln=Er, n=0)

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chinese Journal of Chemistry 1992年第5期10卷 405-411页

作者： jiN, ji-Zhu jiN, Zhong-Sheng WEI, Ge-Cheng CHEN, wen-Qi changchun institute of applied Chemistry, chinese academy of sciences, changchun 13002. changchun institute of {2. Chemistry Chinese Academy of Sciences Changchun 130022

Reactions of lanthanoid trichlorides with sodium cyclopentylcyclopentadienyl in THF afford bis(cyclopentylcyclopentadienyl) lanthanoid chloride complexes (C_5H_9C_5H_4)_2.nCl(THF)_n (Ln= Nd, Sm, n=1; Ln= Er, Yb, n= 0). The compound [CP'_2.mCl(THF)]_2.(2. (Cp' =cyclopentylcy- clopentadienyl) crystallizes from mixed solvent of hexane and THF in monoclinic space group P_2.1/c with a = 11.583 (3), b = 2..019(6), c = 8.2.7 (2.(?), β= 90.2. (2.°, V= 2.94 (1)(?)~3, D_c= 1.59 g/cm^3. μ= 2..6 cm^(-1), F(000) = 1060, Z= 2.(dimers). Its crystal molecule is a dimer with a crystallographic symmetry center. The central metal atom Sm is coordinated to two Cp' rings, two bridging chlorine atoms and one THF forming a distorted trigonal bipyramid. The crystal of [Cp'_2.rCl]_2.(3) belongs to the triclinic space group P(?) with a = 11.2.4 (2., b= 13.2.6(5), c = 14.2.6(6)(?), a = 96.99 (3), β= 112.47(2., γ= 102.78(2.°, V= 1865(1)(?)~3, D_c= 1.67 g /cm^3, μ= 48.0 cm^(-1), F(000) = 92., Z = 2.(dimers). The molecule is a dimer consisting of two Cp'_2.ErCl species bridged by two Cl atoms. The central metal atom Er is coordinated to two Cp' rings and two bridging chlorine atoms forming a pseudo- tetrahedron. All these complexes are soluble in THF, DME, Et_2., toluene and hexane.

关键词： Ln Ln=Nd Ln=Sm n=1 Ln=Er n=0 C5H9C5H4 and crystal structure of THF Yb

High quality repair of osteochondral defects in rats using the extracellular matrix of antler stem cells

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World Journal of Stem Cells 2024年第2期16卷 176-190页

作者： Yu-Su wang wen-Hui Chu {2.ng-{2.e Zhai wen-Ying wang Zhong-Mei He Quan-min Zhao Chun-Yi Li institute of Antler Science and Product Technology Changchun Sci-Tech UniversityChangchun 130000Jilin ProvinceChina College of chinese Medicinal Materials Jilin Agricultural UniversityChangchun 130118Jilin ProvinceChina School of Life Science Taizhou UniversityTaizhou 318000Zhejiang ProvinceChina Department of Oral Implantology Hospital of StomatologyJilin UniversityChangchun 130000Jilin ProvinceChina

BACKGROUND Cartilage defects are some of the most common causes of *** lesions caused by inflammation,trauma or degenerative disease normally result in osteochondral *** studies have shown that decellularized extracellular matrix(ECM)derived from autologous,allogenic,or xenogeneic mesenchymal stromal cells(MSCs)can effectively restore osteochondral *** To determine whether the decellularized ECM of antler reserve mesenchymal cells(RMCs),a xenogeneic material from antler stem cells,is superior to the currently available treatments for osteochondral *** We isolated the RMCs from a 60-d-old sika deer antler and cultured them in vitro to 70%confluence;50 mg/mL L-ascorbic acid was then added to the medium to stimulate ECM *** sheets of adipocyte-derived MSCs(aMSCs)and antlerogenic periosteal cells(another type of antler stem cells)were used as the *** weeks after ascorbic acid stimulation,the ECM sheets were harvested and {2. to the osteochondral defects in rat knee *** The defects were successfully repaired by applying the *** highest quality of repair was achieved in the RMC-ECM group both in vitro(including cell attachment and proliferation),and in vivo(including the simultaneous regeneration of well-vascularized subchondral bone and avascular articular hyaline cartilage integrated with surrounding native tissues).Notably,the antler-stem-cell-derived ECM(xenogeneic)performed better than the aMSC-ECM(allogenic),while the ECM of the active antler stem cells was superior to that of the quiescent antler stem *** Decellularized xenogeneic ECM derived from the antler stem cell,particularly the active form(RMC-ECM),can achieve high quality repair/reconstruction of osteochondral defects,suggesting that selection of decellularized ECM for such repair should be focused more on bioactivity rather than kinship.

关键词： Osteochondral defect repair Mesenchymal stem cells Extracellular matrix Decellularization Antler stem cells Reserve mesenchymal cells Xenogeneic

Study on the Interaction of Rare Earth with 3, 5, 3'-Triiodothyronine

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chinese Chemical Letters 1997年第2期8卷 181-182页

作者： feng GAO Shu yun {2. Shu Lan MENG Yan min LIU Chun ji NIU jia Zuan NI(Laboratory of Rare Earth Chemistry and Physics, changchun institute of Appliet Chemistry, chinese academy of sciences, changchun 13002.) chinese ACAD SCI CHANGCHUN INST APPL CHEMLAB RARE EARTH CHEM & PHYSCHANGCHUN 130022PEOPLES R CHINA

The stability constants for rare earth complexes with 3, 5, 3'-triiodothyronine were determined at 37℃ and an ionic strength of 0.15 mole/L NaCl,The lanthanide induced shifts were measured for 1H nuclei of 3, 5, 3'-t... 详细信息

关键词： 110 Study on the Interaction of Rare Earth with 3

Studies on the Coordination of Pr(Ⅲ) with Adrenaline by Potentiometry and Absorption Spectroscopy

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chinese Chemical Letters 1999年第8期10卷 677-678页

作者： feng GAO jing Fen HAN Zhi jian WU Yue wang kui Yue YANG Chun ji NIU jia Zuan NI (Laboratory of Rare Earth Chemistry and Physics. changchun institute of applied Chemistry. chinese academy of sciences, changchun 13002.) Lab. of Rare Earth Chem. and Physics Changchun Inst. of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

The stability constant for complex of Pr(Ⅲ) with adrenaline has been determined by potentiometric titration under biological conditions (37℃ and 0.15mol/L NaCl). The absorption spectra of the Pr(Ⅲ)-adrenaline system exhibit characteristic bands of Pr(Ⅲ) at lower pH values. However, the charge transfer band which is due to the coordination of Pr(Ⅲ) with adrenaline has been observed at higher pH values.

关键词： Praseodymium adrenaline potentiometry spectroscopy

Synthesis of Novel Cyclic Aryl Ether Thioether Ketone (Sulfone) Oligomers

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chinese Chemical Letters 1998年第7期9卷 615-617页

作者： Ying Hua QI Tian Lu CHEN Hong Yan jiANG Hai Bo LI ji Ping XU ({2. institute of applied Chemistry, chinese academy of sciences, changchun 13002.) chinese Acad Sci Changchun Inst Appl Chem Changchun 130022 Peoples R China

Two kinds of macrocyclic oligomers containing aromatic sulfide linkages have been synthesized by the solution polycondensation in high yield. The cyclic compounds were characterized by H-1 and C-13 NMR, by and MALDI -... 详细信息

关键词： cyclic aryl ether thioether ketone (sulfone) oligomers free radical ROP MALDI

~1H and ^(13)C NMR studies of lanthanide complex with 5-sulfosalicylic acid

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chinese Journal of Chemistry 1990年第6期8卷 512-519页

作者： ren ji-{2. pei feng-kui wang wen-yun Chanchun institute of applied Chemistry Academia SinicaChangchun 130022

In this paper, paramagnetic shifts have been measured for all ~1H and ^(13)C nuclei of 5-sulfo- salicylic acid (SSA) in the presence of the lanthanide ions in the second half of the series. The ligand forms isostructural complexes with these ions in aqueous solution. The separation of LISs was carried out by the use of the Reilley method and the calculated dipolar shifts were used to simulate the coordination structure of the complex. The result reveals that SSA is coordinated to lanthanide ion via two oxygens, one from the carboxylic group and the other from the phenolic group with Ln—O bond lengths equal to 2.47 . The lanthanide ion lies on the benzene plane and the carboxylic group is twisted 2.°from the benzene ring. Of all the nuclei examined, those in the six-membered chelate ring experience significant dipolar interactions and contact interactions. Small |G/A| ratios were obtained for two protons five bonds away from the central lanthanide ion, which shows that the number of bonds alone cannot be used as a criterion for neglecting contact shifts in aromatic ligand.

关键词： than C NMR studies of lanthanide complex with 5-sulfosalicylic acid and NMR