Electroless deposition of Fe-Ni alloys from acidic and alkaline solutions using hypophosphite as a reducing agent

The deposition of Fe?Ni alloys from acidic and alkaline solutions, using hypophosphite as a reducing agent, is studied in this work. The experimental results confirm the autocatalytic nature of this process. The composition of alloys is practically independent of the temperature deposition. Fe?Ni alloys produced from acidic solutions contained less than 1% Fe. The amount of Fe in Fe?Ni alloys produced from alkaline solutions was estimated to be about 15 %. The deposition of Fe?Ni alloys was significantly faster in the alkaline than in the acidic solutions, due to more pronounced hydrolysis of Fe(II) and Ni(II) ions under the alkaline conditions. The Fe?Ni alloys produced from both acidic and alkaline solutions contain phosphorus and as such have amorphous structure.

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Study on the Fabrication and Properties of Ni-P Composite Coating

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.537.265 ◽

2013 ◽

Vol 537 ◽

pp. 265-268

Author(s):

Zhao An ◽

Ming Ya Li ◽

Nian Hao Ge ◽

Xiao Ying Li ◽

Qiu Fan Li ◽

...

Keyword(s):

Crystal Structure ◽

Heat Treatment ◽

Phase Composition ◽

Surface Morphology ◽

Composite Coating ◽

Electroless Deposition ◽

Sample Surface ◽

Reducing Agent ◽

Experimental Results ◽

Complexing Agent

In this paper, the method of electroless deposition of nickel-phosphorous composite coating on the sample surface is employed. The effect of the complexing agent ratio on the surface morphology and phase composition of nickel-phosphorus coating when the main salt and reducing agent concentration unchanged has been studied. The influence of heat treatment on properties and microstructure of coatings are also investigated. Experimental results show that in the case of salt and reducing agent concentration unchanged, complexing agent concentration has strong effect on the morphology of the coatings and the crystal structure of the composite coating. During heat treatment, the morphology of the composite coating changed significantly, and the hardness was improved a certain degree for all the samples, which is related to the precipitation of Ni3P.

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Electroless deposition of copper in acidic solutions using hypophosphite reducing agent

Journal of Applied Electrochemistry ◽

10.1007/s10800-005-9025-7 ◽

2005 ◽

Vol 36 (1) ◽

pp. 69-75 ◽

Cited By ~ 27

Author(s):

R. Touir ◽

H. Larhzil ◽

M. EbnTouhami ◽

M. Cherkaoui ◽

E. Chassaing

Keyword(s):

Electroless Deposition ◽

Reducing Agent ◽

Acidic Solutions

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cis-Activation by Oxyanions Coordinated to Chromium(III): Aquation and Base Hydrolysis of Nitratopentaamminechromium(III) Ion

Canadian Journal of Chemistry ◽

10.1139/v74-083 ◽

1974 ◽

Vol 52 (4) ◽

pp. 527-535 ◽

Cited By ~ 18

Author(s):

Giovanni Guastalla ◽

Thomas Wilson Swaddle

Keyword(s):

Reaction Rate ◽

Base Hydrolysis ◽

Alkaline Solutions ◽

Acidic Solutions ◽

First Order ◽

Order Rate ◽

Rate Of Hydrolysis ◽

Pseudo First Order ◽

Hydrolysis Of

The aquation of Cr(NH3)5NO32+ in acidic solutions yields not only Cr(NH3)5OH23+ (33%) but also more highly aquated species including cis-Cr(NH3)4(OH2)23+ and Cr(NH3)3(OH2)33+. In 0.1 M HClO4, several successive reactions of comparable rates are involved, but at pH 6 only the two competing initial reactions producing Cr(NH3)5OH2+ and cis-Cr(NH3)4(OH)NO3+ are rate-controlling, so that the overall reaction rate is first-order in substrate with the apparent parameters kA = 2.4 × 10−3 s−1(25°), ΔHA* = 20.4 kcal mol−1, and ΔSA* = −2.1 cal deg−1 mol−1. In alkaline solutions, the pseudo-first-order rate of hydrolysis at a given [OH−] is governed by kobs = kA + kOH [OH−], with kOH = 1.1 × 10−2 M−1 s−1 (25°), ΔHOH* = 25.2 kcal mol−1, and ΔSOH* = 17.0 cal deg−1 mol−1. The path characterized by kOH leads exclusively to Cr(NH3)5OH2+. In both aquation and base hydrolysis, it is the Cr—ONO2 bond that is broken. The production of more highly aquated species in the aquation reactions is attributed to transient chelation of NO3− at the expense of a ligand cis to it. The evidence for this mechanism, and for its operation when oxyanions other than nitrate are coordinated to Cr(III), is reviewed.

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Adsorption Synthesis of Iron Oxide-Supported Gold Catalyst under Self-Generated Alkaline Conditions for Efficient Elimination of Carbon Monoxide

Catalysts ◽

10.3390/catal8090357 ◽

2018 ◽

Vol 8 (9) ◽

pp. 357 ◽

Cited By ~ 2

Author(s):

Feng Pan ◽

Weidong Zhang ◽

Yuxiao Ye ◽

Yixuan Huang ◽

Yanzhe Xu ◽

...

Keyword(s):

Carbon Monoxide ◽

Gold Catalyst ◽

Alkaline Solutions ◽

Support Materials ◽

Gold Precursor ◽

Alkaline Conditions ◽

Supported Gold ◽

Hydrolysis Of ◽

Dispersed Gold ◽

Efficient Elimination

Goethite- and hematite-supported highly dispersed gold catalysts for carbon monoxide oxidation were synthesized by gold precursor adsorption onto the support materials in self-generated alkaline solutions. The support materials were prepared by reacting iron nitrate with excess sodium hydroxide. The residual minor alkali incorporated into the support could provide suitable alkaline conditions at approximately pH 8 for the hydrolysis of tetrachloroaurate anions and the subsequent adsorption process. Gold species underwent autoreduction to achieve activation during the synthesis. An increase in pH or temperature to 80 °C decreased the gold loading of the catalysts. The optimal catalysts could achieve complete oxidation of carbon monoxide at −20 °C.

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Spherulite Structures in a Melt Spun Fe-Ni Austenitic Steel

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100117339 ◽

1985 ◽

Vol 43 ◽

pp. 52-53

Author(s):

G. M. Michal ◽

T. K. Glasgow ◽

T. J. Moore

Keyword(s):

Austenitic Steel ◽

Room Temperature ◽

Elevated Temperatures ◽

Large Range ◽

Amorphous Structure ◽

Nucleation And Growth ◽

Ni Alloys ◽

Melt Spun ◽

Crystal Fibers ◽

Rapidly Solidified

Large additions of B to Fe-Ni alloys can lead to the formation of an amorphous structure, if the alloy is rapidly cooled from the liquid state to room temperature. Isothermal aging of such structures at elevated temperatures causes crystallization to occur. Commonly such crystallization pro ceeds by the nucleation and growth of spherulites which are spherical crystalline bodies of radiating crystal fibers. Spherulite features were found in the present study in a rapidly solidified alloy that was fully crysstalline as-cast. This alloy was part of a program to develop an austenitic steel for elevated temperature applications by strengthening it with TiB2. The alloy contained a relatively large percentage of B, not to induce an amorphous structure, but only as a consequence of trying to obtain a large volume fracture of TiB2 in the completely processed alloy. The observation of spherulitic features in this alloy is described herein. Utilization of the large range of useful magnifications obtainable in a modern TEM, when a suitably thinned foil is available, was a key element in this analysis.

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A Study of Catechin Photostability Using Photolytic Processing

Processes ◽

10.3390/pr9020293 ◽

2021 ◽

Vol 9 (2) ◽

pp. 293

Author(s):

Jeu-Ming P. Yuann ◽

Shwu-Yuan Lee ◽

Meei-Ju Yang ◽

Shiuh-Tsuen Huang ◽

Chien-Wei Cheng ◽

...

Keyword(s):

Ascorbic Acid ◽

Superoxide Anion ◽

Anion Radical ◽

Alkaline Solutions ◽

Light Illumination ◽

Drug Resistant ◽

Alkaline Ph ◽

Radical Species ◽

Alkaline Conditions ◽

Photolytic Reaction

Catechin exhibits numerous physiological characteristics. In this study, we determined the photosensitivity of catechin to various lights under alkaline conditions, and the mechanisms by which catechin generates free radical species and polymerizes via a photoreaction. In addition to this, the application of catechin photolysis was investigated. A solution of catechin is transparent, but turns yellowish under blue light illumination (BLI) in neutral or weak alkaline solutions. When catechin is subjected to BLI, a dimeric catechin (proanthocyanidin) and a superoxide anion radical (O2•−) are generated in a photolytic reaction. When ascorbic acid or gallic acid is added to catechin and the mixture is subjected to BLI at alkaline pH, fewer catechin dimers and less O2•− are produced, because both acids inhibit the photosensitive oxidation of catechin. When AlCl3 is added to catechin and the mixture is subjected to BLI at pH 8, a photolytic reaction is suppressed by AlCl3, and AlCl3 acts as a catalyst for the disconnection of proanthocyanidin during photolysis. Under alkaline conditions, catechin generates O2•− via photosensitive oxidation, which suppresses the growth of Acinetobacter baumannii (A. baumannii) by at least 4 logs, and deactivates its multi-drug-resistant strain. This study shows that catechin photolysis is a process of oxidation, and that it can be safely applied as a tool for environmental applications.

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Selective acid hydrolysis of 2,4,6-trimethylbenzyl esters and its application in peptide synthesis

Australian Journal of Chemistry ◽

10.1071/ch9661511 ◽

1966 ◽

Vol 19 (8) ◽

pp. 1511 ◽

Cited By ~ 3

Author(s):

FHC Stewart

Keyword(s):

Acid Hydrolysis ◽

Peptide Synthesis ◽

Trifluoroacetic Acid ◽

Ester Group ◽

Protecting Groups ◽

Alkaline Conditions ◽

Hydrolysis Of

Experiments with various N-acylamino acid 2,4,6-trimethylbenzyl esters have shown that the ester group is cleaved selectively by cold trifluoroacetic acid without affecting benzyloxycarbonyl, formyl, or phthaloyl amino-protecting groups present. The possible value of this selective behaviour in peptide syntheses where the use of alkaline conditions would be detrimental is illustrated by the synthesis of certain dipeptide derivatives.

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