scholarly journals Influence of Synthesis Parameters of FeNi3 Alloy Nanoparticles Obtained by Chemical Reduction Method in Aqueous Solution

2019 ◽  
Vol 70 (4) ◽  
pp. 1118-1124
Author(s):  
Teodora Malaeru ◽  
Eros Alexandru Patroi ◽  
Delia Patroi ◽  
Eugen Manta ◽  
Virgil Marinescu ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Room Temperature ◽  
Chemical Reduction ◽  
Molar Ratio ◽  
Initial Reaction ◽  
Growth Promoter ◽  
Stoichiometric Ratio ◽  
Alloy Nanoparticles ◽  
Face Centered Cubic ◽  
Structural Morphology

This paper reports the synthesis of FeNi3 alloy nanoparticles by chemical reduction of the Fe2+ and Ni2+ ions, from the corresponding chlorides, with hydrazine (N2H4�H2O) as a reducing agent in aqueous solution at room temperature by modifying the molar ratio of the ions Fe2+: Ni2+, reaction time, with and without amine-type growth promoter, and reducing both, with or without ultrasonic aid. The FeNi3 alloy nanoparticles have been investigated by XRD, EDS spectrum analysis, SEM and VSM. When the molar ratio of Fe2+ and Ni2+ is equal to 1:3, reducing both, with or without ultrasonic aid, Fe2+ and Ni2+ were completely reduced into Fe and Ni, resulting FeNi3 alloy with a face-centered cubic (fcc) crystal structure. EDS analysis supported the presence of metal ions in atomic weight corresponding to the stoichiometric ratio of initial reaction. SEM analysis showed that nanoparticles of FeNi3 alloy have a spherical structural morphology. Hysteresis loop show a ferromagnetic behaviour of the FeNi3 alloy nanoparticles at room temperature.

scholarly journals Crystal structure of the new hybrid material bis(1,4-diazoniabicyclo[2.2.2]octane) di-μ-chlorido-bis[tetrachloridobismuthate(III)] dihydrate

2015 ◽  
Vol 71 (11) ◽  
pp. 1384-1387
Author(s):  
Marwen Chouri ◽  
Habib Boughzala
Keyword(s):  
Crystal Structure ◽  
Aqueous Solution ◽  
Hydrogen Bonds ◽  
Room Temperature ◽  
Molar Ratio ◽  
Water Molecules ◽  
Site Symmetry ◽  
Two Dimensional ◽  
Slow Evaporation ◽  
Solution Ph

The title compound bis(1,4-diazoniabicyclo[2.2.2]octane) di-μ-chlorido-bis[tetrachloridobismuthate(III)] dihydrate, (C6H14N2)2[Bi2Cl10]·2H2O, was obtained by slow evaporation at room temperature of a hydrochloric aqueous solution (pH = 1) containing bismuth(III) nitrate and 1,4-diazabicyclo[2.2.2]octane (DABCO) in a 1:2 molar ratio. The structure displays a two-dimensional arrangement parallel to (100) of isolated [Bi2Cl10]4−bioctahedra (site symmetry -1) separated by layers of organic 1,4-diazoniabicyclo[2.2.2]octane dications [(DABCOH2)2+] and water molecules. O—H...Cl, N—H...O and N—H...Cl hydrogen bonds lead to additional cohesion of the structure.

scholarly journals Synthesis of cobalt nanowires in aqueous solution under an external magnetic field

2016 ◽  
Vol 7 ◽  
pp. 990-994 ◽  
Author(s):  
Xiaoyu Li ◽  
Lijuan Sun ◽  
Hu Wang ◽  
Kenan Xie ◽  
Qin Long ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Aqueous Solution ◽  
External Magnetic Field ◽  
Room Temperature ◽  
Magnetic Measurements ◽  
Chemical Reduction ◽  
Average Diameter ◽  
Firm Structure ◽  
Cobalt Nanowires ◽  
First Time

In contrast to the majority of related experiments, which are carried out in organic solvents at high temperatures and pressures, cobalt nanowires were synthesized by chemical reduction in aqueous solution with the assistance of polyvinylpyrrolidone (PVP) as surfactant under moderate conditions for the first time, while an external magnetic field of 40 mT was applied. Uniform linear cobalt nanowires with relatively smooth surfaces and firm structure were obtained and possessed an average diameter of about 100 nm with a coating layer of PVP. By comparison, the external magnetic field and PVP were proven to have a crucial influence on the morphology and the size of the synthesized cobalt nanowires. The prepared cobalt nanowires are crystalline and mainly consist of cobalt as well as a small amount of platinum. Magnetic measurements showed that the resultant cobalt nanowires were ferromagnetic at room temperature. The saturation magnetization (M s) and the coercivity (H c) were 112.00 emu/g and 352.87 Oe, respectively.

Synthesis of NiCu Alloy Nanoparticles by Arc Plasma Evaporation

2013 ◽  
Vol 710 ◽  
pp. 157-160
Author(s):  
Li Xin Li ◽  
Zhong Juan Yang ◽  
Ming Li
Keyword(s):  
Room Temperature ◽  
Raw Materials ◽  
Average Crystallite Size ◽  
Alloy Nanoparticles ◽  
Face Centered Cubic ◽  
Arc Plasma ◽  
Transmission Electron ◽  
Face Centered ◽  
Bulk Alloys ◽  
Microscopy Images

The NiCu nanoparticles were synthesized from NixCu1-x (20 at. % < x < 80 at. %) bulk alloys with arc plasma technique. The experimental results indicated that the crystal structure of the powders is face centered cubic structure, the same as the bulk raw materials. The composition between the prepared powders and the bulk alloys altered with the content of the nickel and copper. With Scherrer equation, the average crystallite size was determined to be 50 nm, which is consistent with the results achieved from the TEM (transmission electron microscopy) images. Also the TEM images showed that some of the nanoparticles could aggregate and grew into micro-size particles at room temperature. The largest size of the grown particle at room temperature was about 1 μm.

scholarly journals Aggregation of Cyanine Dye in Bilayer Vesicles of Phospholipids

2005 ◽  
Vol 4 (3) ◽  
Author(s):  
Casey McCullough ◽  
Matthew Heywood ◽  
Hussein Samha
Keyword(s):  
Aqueous Solution ◽  
Equilibrium Constant ◽  
Room Temperature ◽  
Aggregation Number ◽  
Cyanine Dye ◽  
Molar Ratio ◽  
Isosbestic Point ◽  
Dye Molecules ◽  
Vis Spectroscopy ◽  
J Aggregates

The effect of phospholipid, 1,2-Dipalmitoyl-sn-glycero-3-Phosphocholine (DPPC) on the spectroscopy of the cyanine dye, 1-ethyl-1’-octadecyl-2,2’-cyanine iodide (PIC-18), has been investigated using UV-Vis spectroscopy. Vesicles of DPPC containing PIC-18 in the molar ratio of 1:3 (dye/phospholipids) were prepared in aqueous solution. J-aggregates of PIC-18 were detected in the bilayer wall of the vesicles. When an aqueous solution of mixed PIC-18/DPPC vesicles is treated with excess DPPC vesicles that are prepared separately, the dye molecules in the mixed vesicles underwent a rapid (aggregate)n' n(monomer) equilibrium as the appearance of only one isosbestic point in the absorbance of the dye indicates. The equilibrium constant was calculated at room temperature (Keq = 6.7x10-2). An aggregation number of 4 was calculated for the dye in the bilayer vesicles.

A Co-Promoted Ni-B Amorphous Nanoalloy Catalyst for Liquid Phase Hydrogenation of Furfural to Furfural Alcohol

2011 ◽  
Vol 183-185 ◽  
pp. 2322-2326 ◽  
Author(s):  
Chang Hai Du ◽  
Yong Zhao ◽  
De Sun
Keyword(s):  
Aqueous Solution ◽  
Liquid Phase ◽  
Room Temperature ◽  
Chemical Reduction ◽  
Amorphous Structure ◽  
Cobalt Acetate ◽  
Nickel Acetate ◽  
Liquid Phase Hydrogenation

The Co-promoted Ni-B amorphous nanoalloy catalysts were prepared by the chemical reduction of the aqueous solution containing nickel acetate and cobalt acetate with NaBH4 at room temperature and characterized by BET, XRD and DSC. They were used as catalysts for the liquid phase hydrogenation of furfural to furfural alcohol in alcohol at 353 K under 2.0 MPa of hydrogen. Ni-Co-B catalyst was characterized by XRD as amorphous structure. It was active in the hydrogenation of furfural, and it was significantly more active than Ni-B and Co-B. The optimal Co/ ( Co+Ni ) mole ratio in Ni-Co-B was 0.5.

scholarly journals Photoluminescence characteristics of strontium titanate thin films prepared by spray pyrolysis

2014 ◽  
Vol 10 (2) ◽  
Author(s):  
S. Aisah Mat ◽  
Karim Deraman ◽  
R. Hussin ◽  
W. Nurulhuda W. Shamsuri ◽  
Bakar Ismail ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Aqueous Solution ◽  
Spray Pyrolysis ◽  
Strontium Titanate ◽  
Room Temperature ◽  
Band Gap Energy ◽  
Molar Ratio ◽  
Photoluminescence Spectra ◽  
Gap Energy

Strontium titanate, SrTiO3 thin films were successfully prepared by spray pyrolysis. The strontium titanate, STO precursor solid thin film were fabricated from an aqueous solution of Sr(NO3)2/[(CH3)2CHO]4Ti/HNO3 = 19:1:20 (molar ratio) at room temperature on a substrate. The as-deposited STO thin film with those annealed at different temperature were prepared. Photoluminescence spectra of thin films were obtained using Photoluminescence Spectrophotometer and optical properties were carried out by using Shimadzu Uv-Vis Spectrophotometer. In conclusion, the band gap energy and the bandwidth of thin films have been analysed.  ________________________________________GRAPHICAL ABSTRACT

Fine structural morphology of immunocytes of some molluscs and insects

1990 ◽  
Vol 48 (3) ◽  
pp. 386-387
Author(s):  
S.G. Pal ◽  
G. Baur ◽  
B. Ghosh ◽  
S. Palit ◽  
S. Modak ◽  
...  
Keyword(s):  
Blood Cells ◽  
Phosphate Buffer ◽  
Room Temperature ◽  
Structural Information ◽  
Uranyl Acetate ◽  
Meretrix Meretrix ◽  
Lead Citrate ◽  
Bivalve Molluscs ◽  
Structural Morphology ◽  
Ultrathin Sections

In recent years some of the blood cells of several molluscs and insects are characterised as immunocytes. Similar cells from a few invertebrates from India have been looked into under conventional TEM to register the ultrastructural features. This type of study is first of its kind in the subcontinent. Immunocytes from bivalve molluscs Meretrix meretrix, Laroellidens marqinalis and two insect species, apterygote Ctenolepism a longicaudata and pterygote Gesonula punctifrons provide a new set of fine structural information which forms a basis of comparison with those studied earlier.Immunocytes have been collected from the fresh live species of bivalve molluscs and insects obtained locally at Calcutta. These were fixed in icecold 2% glutaraldehyde in 0.1M phosphate buffer (pH 7.2-7.4) for 1-2 hours at 4-5°C. Subseguently pellets were post-osmicated in 1% OsO4 at room temperature for 1-2 hours. Following dehydration these were embedded in Araldite mixture in plastic capsules and polymerization was effected for 2 days at 60°C. Ultrathin sections were cut in a ultrotome and sections were double stained with Uranyl acetate and lead citrate. These were viewed in a TEM.

Room Temperature Alkali Metal Reduction of Carbon Dioxide

2020 ◽  
Author(s):  
Lucas A. Freeman ◽  
Akachukwu D. Obi ◽  
Haleigh R. Machost ◽  
Andrew Molino ◽  
Asa W. Nichols ◽  
...  
Keyword(s):  
Alkali Metal ◽  
Alkali Metals ◽  
Room Temperature ◽  
Chemical Reduction ◽  
Bond Cleavage ◽  
Open Shell ◽  
Metal Reduction ◽  
One Pot ◽  
Earth Abundant ◽  
Electron Reduction

The reduction of the relatively inert carbon–oxygen bonds of CO<sub>2</sub> to access useful CO<sub>2</sub>-derived organic products is one of the most important fundamental challenges in synthetic chemistry. Facilitating this bond-cleavage using earth-abundant, non-toxic main group elements (MGEs) is especially arduous because of the difficulty in achieving strong inner-sphere interactions between CO<sub>2</sub> and the MGE. Herein we report the first successful chemical reduction of CO<sub>2</sub> at room temperature by alkali metals, promoted by a cyclic(alkyl)(amino) carbene (CAAC). One-electron reduction of CAAC-CO<sub>2</sub> adduct (<b>1</b>) with lithium, sodium or potassium metal yields stable monoanionic radicals clusters [M(CAAC–CO<sub>2</sub>)]<sub>n</sub>(M = Li, Na, K, <b> 2</b>-<b>4</b>) and two-electron alkali metal reduction affords open-shell, dianionic clusters of the general formula [M<sub>2</sub>(CAAC–CO<sub>2</sub>)]<sub>n </sub>(<b>5</b>-<b>8</b>). It is notable that these crystalline clusters of reduced CO<sub>2</sub> may also be isolated via the “one-pot” reaction of free CO<sub>2</sub> with free CAAC followed by the addition of alkali metals – a reductive process which does not occur in the absence of carbene. Each of the products <b>2</b>-<b>8</b> were investigated using a combination of experimental and theoretical methods.<br>

scholarly journals Practical Synthesis of 2-Iodosobenzoic Acid (IBA) without Contamination by Hazardous 2-Iodoxybenzoic Acid (IBX) under Mild Conditions

Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 1897
Author(s):  
Hideyasu China ◽  
Nami Kageyama ◽  
Hotaka Yatabe ◽  
Naoko Takenaga ◽  
Toshifumi Dohi
Keyword(s):  
Aqueous Solution ◽  
Room Temperature ◽  
Practical Method ◽  
Hypervalent Iodine ◽  
Mild Conditions ◽  
Sequential Procedures ◽  
Iodine Compounds ◽  
Practical Synthesis ◽  
Iodosobenzoic Acid ◽  
Lower Temperature

We report a convenient and practical method for the preparation of nonexplosive cyclic hypervalent iodine(III) oxidants as efficient organocatalysts and reagents for various reactions using Oxone® in aqueous solution under mild conditions at room temperature. The thus obtained 2-iodosobenzoic acids (IBAs) could be used as precursors of other cyclic organoiodine(III) derivatives by the solvolytic derivatization of the hydroxy group under mild conditions of 80 °C or lower temperature. These sequential procedures are highly reliable to selectively afford cyclic hypervalent iodine compounds in excellent yields without contamination by hazardous pentavalent iodine(III) compound.

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