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Nickel oxalate nano-fibers were controllably synthesized via a restricted self-assembly growth process in a liquid phase precipitation system. Nickel nano-fibers were prepared by decomposing nickel oxalate under the guidance of fiber micro-structure in Ar gas atmosphere. The characteristics of the samples were measured by X-ray powder diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM). Result show that the existence of ammonia changes the growth behavior of nickel oxalate from free self-assembly mode to a restricted one. The nickel oxalate crystal nano-fibers with monoclinic geometry are 100∼200 nm in diameter, and 1∼5 μm in length. The nickel nano-fibers with face-centered cubic geometry are also 100∼200 nm in diameter, and 1∼5 μm in length, and the surface is very rough. Nickel nano-fibers are formed via a process of nucleation, grain growth and aggregation under the guidance of long and narrow space provided by nickel oxalate nano-fibers. [ABSTRACT FROM AUTHOR]

Submicro-porous nickel wafers were prepared by a molding-decomposition-sintering method, using nickel oxalate nano-rods synthesized via a liquid phase precipitation process as precursors, keeping the decomposition temperature of 360 °C for 10 min, and sintering temperature of 420, 450, 480 and 510 °C for 10 min, in a tubular oven filled with Ar gas. The study of Infrared spectroscopy (IR) indicates that the as-prepared precursor was pure nickel oxalate. The results of X-ray diffractions (XRD) indicate that the as-treated grey wafers were nickel, which has face-centered cubic crystal structure. The images of scanning electron microscopy (SEM) and atomic force microscopy (AFM) show that the morphology of metal nickel wafers exhibit an obvious porous structure. The structure of pores is irregular with 100∼1000 nm in diameter, and the pore walls are composed of fiber-like nickel with 100∼300 nm in diameter. [ABSTRACT FROM AUTHOR]

Metabriggsia ovalifolia W. T.Wang. is an endangered species indigenous to China. Leaf cuttings and petiole segments derived from 1-year-old potted plants, originally derived from in vitro cultures, were used to study the effects of various plant growth regulators (PGRs) and orientation (only for leaf cuttings) on the induction of adventitious shoots and roots. Leaf cuttings and petiole segments dipped in 20.0 μM 6-benzyladenine (BA) for 30 min induced the highest number of shoots per explant (6.8 and 9.8, respectively) among the PGRs tested, and 1 - 20 μM indole-3-butyric acid (IBA) induced more roots than indole-3-acetic acid (IAA) or χ-naphthaleneacetic acid (NAA). Leaf cuttings placed abaxial side down induced significantly more adventitious shoots (5.0 per cutting) than leaf cuttings placed abaxial side up (0.6 per cutting). More than 96% of plantlets survived when transferred to square plastic trays filled with a 1:1 (v/v) mix of sand and perlite. This study provides a simple, quick and efficient method of propagation from leaf cuttings or petiole segments, allowing this endangered ornamental species to be maintained sustainably. [ABSTRACT FROM AUTHOR]

At room temperature, silver nano-sized particles were one-step prepared by a novel facile method of the reduction of silver nitrate with o-Phenylenediamine (o-PD) in a mixed solution of water and N-Methyl-2-pyrrolidone(NMPD). Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were employed to characterize as-prepared silver nanoparticles. The SEM images show that silver nano-particles are well spherical and possessed of uniform particle size, and the average particle size is about 70 nm. The XRD pattern indicates that the values of d hkl , a , and unit cell volume ( V 3 ) of Ag crystal are all a little greater than that of Ag standard card, with face-centred cubic structure. UV-visible spectra (UV-Vs) and liquid chromatography-mass spectrometry (LC-MS) was used to identify the product of oxidation of o-PD in solution after reaction. The results of UV-Vs and LC-MS illustrate that the product of oxidation of o-PD in solution is 2,3-diaminophenazine. [ABSTRACT FROM AUTHOR]

Nano-sized nickel hydroxide particles were synthesized at room temperature by a facile coordination precipitation method, through simply dropping sodium hydroxide solution to dissociate the complex of nickel-hexammonia, using nickel chloride, ammonia and sodium hydroxide as raw materials. Fourier transform infrared spectroscopy (FT-IR), thermo-gravimetry and derivative thermo-gravimetry (TG-DTG), X-ray diffractometry (XRD) and scanning electron microscopy (SEM) were used to characterize the products. It is demonstrated that the product is pure β-type nickel hydroxide, which contains more nickel and fewer intercalated anions comparatively, and likely boosts its electrochemical activity. The average size of β-type nickel hydroxide nano-particles is about 100 nm. [ABSTRACT FROM AUTHOR]

Abstract: Through a mild thermal precipitation and aging process, hydrated cobalt oxalate nanorods were synthesized using CoSO3 and (NH4)2C2O4·H2O as raw materials at the reaction and aging temperature of 65 °C. Afterwards, the metal cobalt nanofibres were prepared by decomposition of cobalt oxalate nanorods precursor in Ar gas atmosphere. The composition and morphology of products were characterized by means of atomic absorption spectrometer (AAS), organic elemental analyzer (OEA), Fourier transform infrared spectroscopy (FT-IR), thermogravimetry analysis and derivative thermogravimetry (TGA-DTG), the X-ray diffraction (XRD), and scanning electron microscope (SEM). The results demonstrate that the product is hydrated cobalt oxalate, and the chemical formula CoC2O4·3H2O is confirmed. The sizes of the cobalt oxalate nanorods as-prepared are about 0.2-0.4 μm in diameter, and 1.0-5.0 μm in length; the metal nanofibres prepared via decomposition process of hydrated cobalt oxalate nanorods are about 0.2 μm in diameter, and 1.0-5.0 μm in length. [Copyright &y& Elsevier]