Shape-Controlled Synthesis and Formation Mechanism of Cobalt Nanopowders by a PVP-Assisted Method

Three different kinds of morphologies including spherical, chainlike and wirelike cobalt nanopowders, have been synthesized by chemical reduction of coblat chloride solution with hydrazine hydrate in basic solution. The products were characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). It was revealed that the morphologies of the nanopowders depend on the concentration of Co2+ and the way of adding reducing agent (hydrazine hydrate). These two features affected the nucleation sites and the number of nucleuses. When the concentration of Co2+ was low, nucleuses formed in the soft template, while the reducing of the reducing agent added drop wise, a little number of nucleuses was formed. Based on that, a mechanism of formation, as a basis of gram-scale syntheses, was proposed.

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The Application of X-Ray Diffraction at Elevated Temperatures to Study the Mechanism of Formation of Sodium Tripolyphosphate

Advances in X-ray Analysis ◽

10.1154/s0376030800001634 ◽

1961 ◽

Vol 5 ◽

pp. 276-284

Author(s):

E. L. Moore ◽

J. S. Metcalf

Keyword(s):

High Temperature ◽

Low Temperature ◽

Amorphous Phase ◽

Elevated Temperatures ◽

Sodium Tripolyphosphate ◽

X Ray Diffraction ◽

Mechanism Of Formation ◽

X Ray ◽

Temperature Form ◽

High Temperature Form

AbstractHigh-temperature X-ray diffraction techniques were employed to study the condensation reactions which occur when sodium orthophosphates are heated to 380°C. Crystalline Na4P2O7 and an amorphous phase were formed first from an equimolar mixture of Na2HPO4·NaH2PO4 and Na2HPO4 at temperatures above 150°C. Further heating resulted in the formation of Na5P3O10-I (high-temperature form) at the expense of the crystalline Na4P4O7 and amorphous phase. Crystalline Na5P3O10-II (low-temperature form) appears after Na5P3O10-I.Conditions which affect the yield of crystalline Na4P2O7 and amorphous phase as intermediates and their effect on the yield of Na5P3O10 are also presented.

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Morphological Characterization of Shape-Controlled TiO2 Anatase through XRPD Analysis

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2015-0715 ◽

2016 ◽

Vol 230 (9) ◽

Cited By ~ 2

Author(s):

Mauro Coduri ◽

Michela Maisano ◽

Maria Vittoria Dozzi ◽

Elena Selli

Keyword(s):

Morphological Characterization ◽

Morphological Investigation ◽

X Ray Diffraction ◽

Preferential Growth ◽

Rietveld Refinements ◽

X Ray ◽

Tio2 Anatase ◽

Shape Controlled ◽

Scherrer Equation

AbstractPreferential growth of anatase crystallites along different directions is known to deeply affect their photocatalytic properties, especially with respect to the exposure of the reactive {001} facets. Its extent can be easily quantified through simple geometric calculations, on the basis of crystal sizes extracted for specific directions by means of X-Ray Diffraction data analysis. Nevertheless, the actual results depend on the method employed for such a quantification. Here we report on a comparative morphological investigation, performed by employing the Scherrer equation and the line profile from Rietveld refinements, on shape-controlled anatase photocatalysts produced by employing HF as capping agent. Compared to the Rietveld-based method, the use of the Scherrer equation produces a systematic underestimation of crystallite dimensions, especially concerning the [100] direction, which in turn causes the percentage of exposed {001} crystal facets to be underestimated. Neglecting instrumental-related effects may further reduce the estimate.

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A study concerning the pretreatment of CNTs and its influence on the performance of NIB/CNTs amorphous catalyst

Journal of the Serbian Chemical Society ◽

10.2298/jsc0611153h ◽

2006 ◽

Vol 71 (11) ◽

pp. 1153-1160 ◽

Cited By ~ 6

Author(s):

Chang Hu-Yuan ◽

Feng Li ◽

Li. Hua ◽

Bin Zhang

Keyword(s):

Selective Hydrogenation ◽

Inductively Coupled Plasma ◽

Acid Treatment ◽

Chemical Reduction ◽

X Ray Diffraction ◽

Chemical Reduction Method ◽

X Ray ◽

Inductively Coupled ◽

Selective Hydrogenation Of Acetylene ◽

Transmission Electron

As prepared carbon nanotubes were pretreated with nitric acid (CNTs-HNO3) or ammonia (CNTs-NH3). Fourier transform infrared spectroscopy (FTIR) measurements showed that the surface of the nanotubes was functionalized with carboxylic and hydroxyl functional groups after the acid treatment and that basic groups containing nitrogen, such as N-H and C-N, were introduced to the surface of the nanotubes after the ammonia treatment. X-Ray diffraction analysis implied that the nickel residue in the CNTs was effectively removed by acid treatment. However, the nickel residue was only partially eliminated by ammonia pretreatment. NiB amorphous catalysts supported on CNTs-HNO3 and CNTs-NH3 were prepared by the impregnation-chemical reduction method and characterized by transmission electron microscopy (TEM), as well as inductively coupled plasma (ICP) spectroscopy and studied in the selective hydrogenation of acetylene. TEM measurements showed that a high density NiB particles of about 9 nm were homogeneously dispersed on the CNTs-NH3. However, NiB particles (13-23 nm)with amean size of 16 nm were scattered on the CNTs-HNO3.As a result, the activity and selectivity of NiB/CNTs-NH3 were higher than those of NiB/CNTs-HNO3 in the selective hydrogenation of acetylene.

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Nickel-phenanthroline Complex Supported on Mesoporous Carbon as a Catalyst for Carboxylation under CO2 Atmosphere

BULLETIN OF CHEMICAL REACTION ENGINEERING AND CATALYSIS ◽

10.9767/bcrec.16.1.9733.111-119 ◽

2021 ◽

Vol 16 (1) ◽

pp. 111-119

Author(s):

Iman Abdullah ◽

Riri Andriyanti ◽

Dita Arifa Nurani ◽

Yuni Krisyuningsih Krisnandi

Keyword(s):

Mesoporous Carbon ◽

Nickel Complex ◽

Solid Support ◽

Soft Template ◽

X Ray Diffraction ◽

X Ray ◽

Ft Ir ◽

Phenanthroline Complex ◽

Temperature Time ◽

Open Access Article

Carbon dioxide is a highly potential renewable C1 source for synthesis of fine chemicals. Utilization of CO2 in carboxylation reactions requires catalysts, such as: nickel complex for CO2 activation. However, the use of homogeneous catalysts in the reaction is still less efficient due to the difficulty of separating the product and catalyst from reaction mixture. Therefore, it is necessary to heterogenize the nickel complex in a solid support such as mesoporous carbon. In this report, mesoporous carbon (MC) prepared from phloroglucinol and formaldehyde through soft template method was used as a solid support for Ni-phenanthroline complex (Ni-phen). The catalyst was characterized by Fourier Transform Infra Red (FT-IR), X-Ray Diffraction (XRD), Scanning Electron Microscope - Energy Dispersive X-Ray (SEM-EDX), and Surface Area Analyzer (SAA). The result of SAA characterization showed that the pore diameter of MC was 6.7 nm and Ni-phen/MC was 5.1 nm which indicates that the materials have meso-size pores. Ni-phen/MC material was then used as a heterogeneous catalyst in the carboxylation reaction of phenylacetylene under an ambient CO2 pressure. The reactions were carried out in several variations of conditions such as temperature, time and catalyst types. Based on the results of the reaction, the best conditions were obtained at 25 °C for 8 h of reaction time using Ni-phen/MC catalyst. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

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THE COMPOSITION, STRUCTURE, AND MECHANISM OF FORMATION OF THE LINING OF THE GIZZARD OF THE CHICKEN

Canadian Journal of Biochemistry ◽

10.1139/o64-006 ◽

1964 ◽

Vol 42 (1) ◽

pp. 59-70 ◽

Cited By ~ 4

Author(s):

T. E. Webb ◽

J. Ross Colvin

Keyword(s):

Electron Microscope ◽

Sedimentation Coefficient ◽

Performic Acid ◽

X Ray Diffraction ◽

Mechanism Of Formation ◽

Protein Layer ◽

Covalent Bonds ◽

X Ray ◽

Disulphide Bonds ◽

Composition Structure

The extracellular protein layer which surrounds the lumen of the gizzard of the chicken has been reinvestigated to determine if it is a keratin. The lining is insoluble in keratin solvents such as urea-bisulphite or Swan's reagent as well as thioglycollate and performic acid. In addition, it contains only 1.45% sulphur so that disulphide bonds cannot play a major role in its consolidation. The lining is insoluble in acids but readily dispersed in alkali without breaking of covalent bonds. The dispersion in alkali is retarded by electrolytes. The lining is hydrolyzed by trypsin and chymotrypsin at pH 8.0 but is resistant to pepsin at pH 2.0. An alkaline dispersion of the lining is heterogeneous in the ultracentrifuge, but not grossly so, with a mean sedimentation coefficient of 5.6 svedbergs. Electron microscope studies of the lining suggest it is an amorphous, precipitated protein, which is consistent with the observation of three hazy rings in X-ray diffraction powder patterns reflecting spacings of 3.5, 4.6, and 9.4 Å. Amino acid analysis shows a ratio of more than three acidic groups to one basic, with no carbohydrate residues and little lipid in the protein layer. These observations are interpreted as indicating the precipitation of an amorphous, non-keratin, acidic, abrasion-resistant protein from the glandular mucosa by the acid in the gizzard.

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Facile synthesis of water-soluble graphene-based composite: Non-covalently functionalized with chitosan-ionic liquid conjugation

Functional Materials Letters ◽

10.1142/s1793604716500454 ◽

2016 ◽

Vol 09 (03) ◽

pp. 1650045 ◽

Cited By ~ 7

Author(s):

Pei-Ying Li ◽

Kai-Yu Cheng ◽

Xiu-Cheng Zheng ◽

Pu Liu ◽

Xiu-Juan Xu

Keyword(s):

Electron Microscopy ◽

Ionic Liquid ◽

Chemical Reduction ◽

Water Soluble ◽

X Ray Diffraction ◽

Facile Synthesis ◽

X Ray ◽

Transmission Electron ◽

Vis Spectroscopy ◽

Text Interaction

Chitosan-ionic liquid conjugation (CILC), which was prepared through the reaction of 1-(4-bromobutyl)-3-methylimidazolium bromide (BBMIB) with chitosan, was firstly used to prepare functionalized graphene composite via the chemical reduction of graphene oxide (GO). The obtained water soluble graphene-based composite was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), ultraviolet-visible (UV–Vis) spectroscopy and so on. CILC-RGO showed excellent dispersion stability in water at the concentration of 2.0 mg/mL, which was stable for several months without any precipitate. This may be ascribed to the electrostatic attraction and [Formula: see text]–[Formula: see text] interaction between CILC and graphene.

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Preparation of Ni-Coated SiC Ceramic Composite Powder by Electroless Plating

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.117-119.77 ◽

2011 ◽

Vol 117-119 ◽

pp. 77-80

Author(s):

Huai Yao ◽

Guang Lin Zhu ◽

Yong Zhi Wang

Keyword(s):

Electroless Plating ◽

Ph Value ◽

Nickel Chloride ◽

Gas Production ◽

Basic Solution ◽

X Ray Diffraction ◽

X Ray ◽

Deep Blue ◽

Reaction Theory ◽

Diffraction Patterns

As a surface technology, electroless plating is applied to almost every industry branch. To improve the wettability of SiC powder and metal, the surface of SiC powders was plated with a Ni plating in the basic solution according to the reaction theory of electroless plating. The main salting was nickel chloride, and the reducing agent was hydrazine hydrate. The plating velocity, phase transformation and microstructurewere investigated using XRD and SEM. The results show that the SiC powders had no increasing weight and no reaction can occur when the pH below 8.5. when the pH value was between 10 and 11, the weight gain of powders closed to the theoretical value, the Ni peaks in X-ray diffraction patterns of powders was relatively strong, the SiC coating surface was composed of granular, cellular and globe-like Ni, the substrate was covered of Ni plating completely. When the pH value was above 11, the gas production was becoming more pronounced and the reaction speed increasing with the increased of the pH value, the time from deep blue to colorless of solution started to drop off, the Ni(OH)2peaks in X-ray diffraction patterns of powders have already begun to emerged and a small amount of nickel films was generated.

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Green Synthesis of Novel Jasmine Bud-Shaped Copper Nanoparticles

Journal of Nanotechnology ◽

10.1155/2014/626523 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 26

Author(s):

Malathi Sampath ◽

Ramya Vijayan ◽

Ezhilarasu Tamilarasu ◽

Abiraman Tamilselvan ◽

Balasubramanian Sengottuvelan

Keyword(s):

Copper Nanoparticles ◽

Isonicotinic Acid ◽

Chemical Reduction ◽

Average Particle Size ◽

Acid Hydrazide ◽

Reducing Agent ◽

Average Particle ◽

X Ray Diffraction ◽

Atomic Force ◽

Transmission Electron

Novel jasmine bud-shaped copper nanoparticles were synthesized by a green chemical reduction method using polyvinylpyrrolidone (PVP) as a capping agent, L-ascorbic acid (AA) as a reducing agent as well as antioxidant agent, isonicotinic acid hydrazide (INH) as a reducing agent, and water as a solvent at 60–70°C (pH-7) in the presence of air. The UV-Vis absorption maximum obtained is 573 nm. The crystal lattice (fcc) structure of Cu Nps was confirmed by X-ray diffraction (XRD). The novel jasmine bud shape was visualized in a transmission electron microscope (TEM). The height of single copper nanobud was 6.41 nm as measured by atomic force microscope (AFM). The average particle size 6.95 nm is obtained by XRD results. Antibacterial activity of the Cu nanobuds was evaluated by testing against Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria.

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Synthesis of Ag Nanoparticles-Clinoptilolite Composite by Homogeneous and Heterogeneous Nucleation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.755.97 ◽

2013 ◽

Vol 755 ◽

pp. 97-103 ◽

Cited By ~ 2

Author(s):

A. Ruíz-Baltazar ◽

R. Esparza ◽

R. Pérez ◽

G. Rosas

Keyword(s):

Silver Nitrate ◽

Sodium Borohydride ◽

Heterogeneous Nucleation ◽

Ag Nanoparticles ◽

Natural Zeolite ◽

Colloidal Solution ◽

Chemical Reduction ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron

In this study, a natural zeolite clinoptilolite-type was impregnated through homogeneous and heterogeneous nucleation with silver nanoparticles. The synthesis of Ag nanoparticles was carried out by chemical reduction of silver nitrate (AgNO3) with sodium borohydride (NaBH4). In the case of homogeneous nucleation, colloidal solution of Ag nanoparticles at concentrations of 1, 2 and 4 parts per million was added and magnetically mixed with the porous material. With respect to heterogeneous nucleation, a solution of clinoptilolite and silver nitrate (0.01 M) was prepared and stirred; subsequently, the reduction of Ag was possible due to the addition of an aqueous solution of sodium borohydride. For the structural characterization, transmission electron microscopy (TEM), X-ray diffraction (XRD) and infrared spectroscopy (IR) techniques were carried out. The results were compared and discussed in both types of nucleation.

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