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Synthesis and characterization of multiferroic BiMn$_7$O$_{12}$  [PDF]
F. Mezzadri,G. Calestani,M. Calicchio,E. Gilioli,F. Bolzoni,R. Cabassi,M. Marezio,A. Migliori
Physics , 2008, DOI: 10.1103/PhysRevB.79.100106
Abstract: We report on the high pressure synthesis of BiMn$_7$O$_{12}$, a manganite displaying a "quadruple perovskite" structure. Structural characterization of single crystal samples shows a distorted and asymmetrical coordination around the Bi atom, due to presence of the $6s^{2}$ lone pair, resulting in non-centrosymmetric space group Im, leading to a permanent electrical dipole moment and ferroelectric properties. On the other hand, magnetic characterization reveals antiferromagnetic transitions, in agreement with the isostructural compounds, thus evidencing two intrinsic properties that make BiMn$_7$O$_{12}$ a promising multiferroic material.
Synthesis and Characterization of AlB12 Nanorods
XU Jun-Qi, WANG Yan-Rui, ZHAO Yan-Ming, YU Ben-Hai, LUO Yong-Song, SUN Hai-Bin
无机材料学报 , 2010, DOI: 10.3724/sp.j.1077.2010.00857
Abstract: Chemical vapor deposition (CVD) method was utilized to synthesize single-crystal AlB12 nanorods on Si substrates in the high temperature horizontal furnace under H2 and Ar atmosphere, using Al powders and BCl3 gas as precursors without any catalysts. The morphology, crystal structures and components of the AlB12 were examined by scanning electron microscope (SEM), high-resolution transmission electron microscope (HRTEM), selected-area electron diffraction(SAED) and energy disperse spectrometer (EDS). SEM shows that the as-synthesized nanowires with the diameter ranging from 100nm to 350 nm and length ranging from several nanometers to several micrometers. HRTEM, SAED, and EDS reveal that the AlB12 nanorods are crystals elongated along the [020] direction. And growth mechanism based on the self-catalyst process is proposed for the formation of the AlB12 nanorods.
SYNTHESIS, CHARACTERIZATION AND BIOLOGICAL EVALUATION OF A Fe3O4/C12 CORE/SHELL NANOSYSTEM
Alexandru Mihai Grumezescu,Ecaterina Andronescu,Anton Ficai,Dan Eduard Mihaiescu
Letters in Applied NanoBioScience , 2012,
Abstract: Lauric acid (C12) functionalized Fe3O4 nanoparticles were fabricated and characterized by XRD, FT-IR, DTA-TG and TEM. Lauric acid was used as a coating agent, controlling particle size and aggregation during the synthesis. XRD confirms the formation of magnetite. FT-IR evidenced the successful surface fictionalization with C12, peaks assigned to lauric acid being identified in the nanopowder. The obtained core/shell nanostructure consists of spherical particles of several nanometers long, according to TEM characterization. The interaction with HEp2 cell line proved that Fe3O4/C12 nanostructures are biocompatible.
RHEOLOGICAL PHASE SYNTHESIS AND CHARACTERIZATION OF MICRO-SIZED Li4Ti5O12
XIE,LINGLING; CAO,XIAOYU; LIU,CHANGWEI; WANG,CHIWEI;
Journal of the Chilean Chemical Society , 2010, DOI: 10.4067/S0717-97072010000300015
Abstract: zero-strain anode material of li4ti5o12 for lithium ion battery was successfully synthesized via the rheological phase reaction (rpr) method. the as-prepared powders were characterized by means of powder x-ray diffraction (xrd), scanning electron microscope (sem) and particle size distribution analysis (psd), and the electrochemical properties of the powders were evaluated by the galvanostatic discharge test and cyclic voltammetry (cv). the results revealed that well-crystallized uniform micro-sized li4ti5o12 powders were obtained at 800°c for different calcination times via the simple template-free rheological phase route. among these rpr-derived li4ti5o12 powders, one synthesized at 800°c for 22 h displays the initial discharge capacity of 184.3 mah/g and excellent characteristic of cyclic voltammetry.
RHEOLOGICAL PHASE SYNTHESIS AND CHARACTERIZATION OF MICRO-SIZED Li4Ti5O12  [cached]
LINGLING XIE,XIAOYU CAO,CHANGWEI LIU,CHIWEI WANG
Journal of the Chilean Chemical Society , 2010,
Abstract: Zero-strain anode material of Li4Ti5O12 for lithium ion battery was successfully synthesized via the rheological phase reaction (RPR) method. The as-prepared powders were characterized by means of powder X-ray diffraction (XRD), scanning electron microscope (SEM) and particle size distribution analysis (PSD), and the electrochemical properties of the powders were evaluated by the galvanostatic discharge test and cyclic voltammetry (CV). The results revealed that well-crystallized uniform micro-sized Li4Ti5O12 powders were obtained at 800°C for different calcination times via the simple template-free rheological phase route. Among these RPR-derived Li4Ti5O12 powders, one synthesized at 800°C for 22 h displays the initial discharge capacity of 184.3 mAh/g and excellent characteristic of cyclic voltammetry.
In-situ synthesis and characterization of polyaniline -CaCu3Ti4O12 nano crystal composites  [PDF]
P. Thomas,K. Dwarakanath,K. B. R. Varma
Physics , 2013, DOI: 10.1016/j.synthmet.2009.08.001
Abstract: High dielectric constant nano composite of Polyaniline (PANI) CaCu3Ti4O12 (CCTO) was synthesized using a simple procedure involving in-situ polymerization of aniline in dil. HCl. The PANI and the composite were subjected to X-ray diffraction, Fourier transform infrared, Thermo gravimetric, Scanning electron microscopy and Transmission electron microscopy analyses. The presence of the nano crystallites of CCTO embedded in the nanofibers of PANI matrix was established by TEM. Frequency dependent characteristics of the dielectric constant, dielectric loss and AC conductivity were studied for the PANI and the composites. The dielectric constant increased as the CCTO content increased in PANI but decreased with increasing frequency of measurement. The dielectric loss was two times less than the value obtained for pure PANI around 100Hz. The AC conductivity increased slightly upto 2kHz as the CCTO content increased in the PANI which was attributed to the polarization of the charge carriers.
Synthesis, structural characterization and formation mechanism of giant-dielectric CaCu3Ti4O12 nanotubes  [PDF]
Nirupam Banerjee, Saluru Baba Krupanidhi
Natural Science (NS) , 2010, DOI: 10.4236/ns.2010.27085
Abstract: A capillary-enforced template-based method has been applied to fabricate calcium copper titanate (CaCu3Ti4O12, CCTO) nanotubes (diameter ~200 nm) by filling sol-gel CCTO precursor solution into the nanochannels of porous anodic aluminum oxide (AAO) templates, subsequent heating for phase formation and fi- nally the removal of nano-channel templates by applying basic solution. X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) equipped with Energy-dispersive X-ray spectroscopy (EDX) have been employed to characterize the morphology, structure, and composition of as-prepared nanotubes. XRD and selected-area electron diffraction (SAED) in-vestigations demonstrated that postannealed (750○C for 1 h) CCTO nanotubes were poly-crystalline with a cubic pseudo-perovskite cry- stal structure. The FE-SEM and TEM results showed that CCTO nanotubes were of uniform diameter (~200 nm) throughout their length. High resolution TEM (HRTEM) analysis confirm- ed that the obtained CCTO nanotubes are made of randomly aligned nano-particles 5-10 nm in size. EDX analysis demonstrated that stoichi- ometric CaCu3Ti4O12 was formed. The possible formation mechanism of CCTO nanotubes in the AAO template is discussed.
The Research for APG-12 Emulsifying Properties  [PDF]
Jigang Wang, Sitong Chen, Yongle Xin, Yong’an Wang
Open Journal of Composite Materials (OJCM) , 2015, DOI: 10.4236/ojcm.2015.51004
Abstract: Through determining and evaluating interfacial tension and emulsifying properties of dodecyl polyglucoside (APG-12), the results show that APG-12’s performance is better than C12 linear alkylbenzene sulfonate (LAS) and alkyl phenol polyoxyethylene ether (OP-10). In order to emulsify properties of APG-12, it is more stable when concentration is over 1.5 g/L. We studied the temperature and oil-water ratio has an effect on emulsifying property.
Synthesis and characterization of [Cd8Cl2Se(SePh)12(PCy3)2]·2.5CH3OH
Stieler, Rafael;Bublitz, Fabrício;Burrow, Robert A;Oliveira, Gelson N. Manzoni de;Villetti, Marcos A;Pereira, Marcelo B;Piquini, Paulo;Lang, Ernesto S;
Journal of the Brazilian Chemical Society , 2010, DOI: 10.1590/S0103-50532010001100017
Abstract: in this article we present the synthesis of the compound [cd8cl2se(seph)12(pcy3)2]·2.5ch3oh by the reaction of cd(seph)2 with cdcl2 and pcy3 in methanol in a stainless steel sealed reactor under solvothermal conditions at 130 oc. this compound represents the latest result of our systematic work on the growth of molecular clusters from cd(seph)2 as starting material. their importance is based not only on the properties of the new compounds, but also by their possible use, for example, in the development of new methods via a ''bottom up" strategy to obtain different clusters from single components like m(er)2 (m = metal, e = chalcogen, r = alkyl or aryl). the title compound was characterized by single crystal x-ray diffractometry, elemental analysis, thermogravimetrical analysis and the uv-vis spectroscopy. these results were correlated with data calculated by dft, density functional theory.
Biogenic synthesis and characterization of gold nanoparticles by Escherichia coli K12 and its heterogeneous catalysis in degradation of 4-nitrophenol
Sarvesh Kumar Srivastava, Ryosuke Yamada, Chiaki Ogino and Akihiko Kondo
Nanoscale Research Letters , 2013, DOI: 10.1186/1556-276X-8-70
Abstract: Room-temperature extracellular biosynthesis of gold nanoparticles (Au NPs) was achieved using Escherichia coli K12 cells without the addition of growth media, pH adjustments or inclusion of electron donors/stabilizing agents. The resulting nanoparticles were analysed by ultraviolet–visible (UV–vis) spectrophotometry, atomic force microscopy, transmission electron microscopy and X-ray diffraction. Highly dispersed gold nanoplates were achieved in the order of around 50 nm. Further, the underlying mechanism was found to be controlled by certain extracellular membrane-bound proteins, which was confirmed by Fourier transformation-infrared spectroscopy and sodium dodecyl sulfate polyacrylamide gel electrophoresis. We observed that certain membrane-bound peptides are responsible for reduction and subsequent stabilization of Au NPs (confirmed by zeta potential analysis). Upon de-activation of these proteins, no nanoparticle formation was observed. Also, we prepared a novel biocatalyst with Au NPs attached to the membrane-bound fraction of E. coli K12 cells serving as an efficient heterogeneous catalyst in complete reduction of 4-nitrophenol in the presence of NaBH4 which was studied with UV–vis spectroscopy. This is the first report on bacterial membrane-Au NP nanobiocomposite serving as an efficient heterogeneous catalyst in complete reduction of nitroaromatic pollutant in water.
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