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101.
Jin-Ju Nie Yan-Tuan Li Xiao-Wen Li Zhi-Yong Wu Cui-Wei Yan 《Transition Metal Chemistry》2011,36(4):341-349
Two tetranuclear copper(II) complexes bridged by asymmetrical N,N′-bis(substituted)oxamides have been synthesized and characterized as [Cu4(dmapob)2(Me2bpy)2](pic)2·6H2O (1) and [Cu4(oxbe)2(dabt)2](pic)2 (2), where H3dmapob and H3oxbe denote N-benzoato-N′-[3-(dimethylamino)propyl]oxamido and N-benzoato-N′-(2-aminoethyl)oxamide, respectively; and Me2bpy, dabt, and pic represent 4,4′-dimethyl-2,2′-bipyridine 2,2′-diamino-4,4′-bithiazole, and 2,4,6-trinitrophenol, respectively.
Complex 1 was characterized by elemental analyses, IR and electronic spectra, and single-crystal X-ray diffraction. Its structure consists
of two asymmetrical binuclear copper(II) units linked by carboxyl bridges into a circular tetranuclear copper(II) complex
with an embedded center of inversion. The copper(II) centers are in square-planar and distorted square-pyramidal environments.
Hydrogen bonds and aromatic stacking interactions link the tetranuclear copper(II) fragments into a 3D supramolecular structure.
The interactions of complexes 1 and 2 with herring sperm DNA (HS-DNA) were investigated by electronic and fluorescence spectra and viscosity measurements. Both
complexes bind to HS-DNA via the intercalative mode, and complex 2 displays a significant binding propensity to HS-DNA. 相似文献
102.
Jing Hua Zhongguang Wang Jian Zhao Jin Zhang Ruying Li Hengyong Nie Xueliang Sun 《Colloid and polymer science》2011,289(7):783-789
A facile approach to attach high-density and uniform gold nanoparticles on individual multi-walled carbon nanotubes (MWNTs)
is achieved. By simple grinding, water-soluble linear polymers poly(4-vinylpyridine) (PVP)-wrapped around nanotubes and thus
rendered them reversibly soluble in water, ethanol, and DMF. Individual tubes are clearly observed after PVP-wrapped nanotubes
were spin-coated onto a silicon wafer. Subsequently, Au nanoparticles were densely decorated on the individual MWNTs by in
situ reduction of HAuCl4 in the homogeneous aqueous solution of MWNTs–PVP to form stable water-dispersible Au/PVP/MWNTs hybrid. Morphology of Au nanoparticles
was determined by scanning electron microscope and atomic force microscope. The diameter of the Au nanoparticles is controlled
in the range of 3.5 to 13.5 nm. The presence of gold nanoparticles with decreased particle size was also detected by UV–Vis
spectroscopy. 相似文献
103.
104.
105.
Electrospinning is known to be a highly versatile method to produce nanofibers, and several techniques have been developed
to align nanofibers. In this paper, poly(vinyl alcohol) (PVA), poly(vinylpyrrolidone) (PVP), poly(propylene carbonate) (PC),
poly(ethylene oxide) (PEO), PVA/Chitosan and PVA/Fe3O4 uniaxially aligned ultrafine fibers were obtained with electrospinning method by adding another electric field in the collection
area. Alignment of the nanofibers was characterized by the use of digital cameras and field emission scanning electron microscopy,
polarized Fourier transform infrared spectroscopy (FTIR), and wideangle X-ray diffraction (XRD). The mechanism of fiber alignment
was investigated as well. 相似文献
106.
A photopolymerizationable mimic mussel protein structure monomer, dopamine methacrylamide (DMA), was synthesized. The photopolymerization
of DMA was analysed by series real time near infrared spectroscopy (SRTIR). Dopamine methacrylamide/poly (ethylene oxide)
(DMA/PEO) nanofibers were successfully prepared by electrospinning of aqueous DMA/PEO solution. Biocompatible nanofibrous
membrane with good adhesion was produced by photocuring from the DMA/PEO nanofibers. The surface characterization and structure
of the composite nanofibrous membrane were characterized by a scanning electron microscopy (SEM) and contact angle measurements.
For identifying the potential crystalline of curing, a XRD method was used through comparing diffraction data. In the cell
adhesion test we utilized the mouse fibroblast (L929) to exam the various use of the nanofibrous membrane as scaffolding materials
for skin regeneration. 相似文献
107.
The electronic coupling between two amine redox sites bridged through the 5,5′‐positions of the [Re(CO)3Cl]‐chelated 2,2′‐bipyridine was studied by the electrochemical, spectroscopic, and EPR analysis. Interestingly, multiple near‐infrared bands were observed in this new organic mixed‐valent system. The results are interpreted with the aid of DFT and TDDFT calculations. 相似文献
108.
Junlin Gao Jun Wang Jianhua Nie 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(6):m181-m184
The title dicadmium compound, [Cd2(C10H8N2)5(H2O)6](C7H6NO2)2(ClO4)2·2H2O, is located around an inversion centre. Each CdII centre is coordinated by three N atoms from three different 4,4′‐bipyridine ligands and three O atoms from three coordinating water molecules in a distorted octahedral coordination environment. In the dicadmium cation unit, one 4,4′‐bipyridine (4,4′‐bipy) molecule acts as a bidentate bridging ligand between two Cd metal ions, while the other four 4,4′‐bipy molecules act only as monodentate terminal ligands, resulting in a rare `H‐type' [Cd2(C10H8N2)5(H2O)6] host unit. These host units are connected to each other viaπ–π stacking interactions, giving rise to a three‐dimensional supramolecular grid network with large cavities. The 3‐aminobenzoate anions, perchlorate anions and water molecules are encapsulated in the cavities by numerous hydrogen‐bonding interactions. To the best of our knowledge, this is the first example of a coordination compound based on both 4,4′‐bipyridine ligands together with discrete 3‐aminobenzoate anions. 相似文献
109.
Jiajing Wu Dr. Jianyu Tong Dr. Yuan Gao Dr. Aifei Wang Prof. Tao Zhang Prof. Hairen Tan Prof. Shuming Nie Prof. Zhengtao Deng 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(20):7812-7816
A novel triphenylphosphine (TPP) treatment strategy was developed to prepare the near-infrared emission CsPbI3 nanocrystal (NC)-polymer composite thin-film luminescent solar concentrators (LSCs) featuring high absolute photoluminescence quantum yield (PLQY), low reabsorption, and high stability. The PL emission of the LSCs is centered at about 700 nm with 99.4±0.4 % PLQY and narrow full width at half maximum (FWHM) of 75 meV (30 nm). Compared with LSCs prepared with classic CsPbI3 NCs, the stability of the LSCs after TPP treatments has been greatly improved, even after long-term (30 days) immersion in water and strong mercury-lamp irradiation (50 mW cm−2). Owing to the presence of lone-pair electrons on the phosphorus atom, TPP is also used as a photoinitiator, with higher efficiency than other common photoinitiators. Large-area (ca. 75 cm2) infrared LSCs were achieved with a high optical conversion efficiency of 3.1 % at a geometric factor of 10. 相似文献
110.
作者以聚四氟乙烯(PTFE)为固体润滑剂填料对GM型齿轮润滑成膜膏进行了改进,并且研制出了两种新的成膜膏系列产品。经四球试验机、动静摩擦系数精密测定仪和SRV试验机评价的结果表明,添加PTFE的GM-2型成膜膏的承载能力和减磨性能都明显地比未添加的好;以PTFE为主要固体润滑剂填料的GM-3和MFC-1型两种润滑成膜膏也都具有良好的润滑性能,其中后者的性能与含PTFE的GM-2型成膜膏的接近。通过对摩擦轨迹的电子探针检测发现,PTFE在摩擦过程中于摩擦表面形成了转移膜,因而改善了润滑成膜膏的摩擦学性能。 相似文献