The Study on the Dispersants and Structures of Ni-P-α-Al2O3 Composite Electroless Plating Coating

2008 ◽  
Vol 373-374 ◽  
pp. 281-284 ◽  
Author(s):  
Li Ming Feng ◽  
Ke Gao Liu ◽  
X.F. Guo
Keyword(s):  
Electroless Plating ◽  
Ordinary Condition ◽  
Nickel Matrix ◽  
Optimum Conditions ◽  
Sem Images ◽  
Base Solid Solution ◽  
The Stability ◽  
Α Al2o3 ◽  
Dispersing Ability ◽  
Emulsifying Ability

Dispersants are selected and optimized by determining the height of emulsion in the colorimetric cylinder after standing in order to ensure the homogeneity of the powder and the stability of electroless plating solution. Experimental results show that non-ionic surfactants such as PEG6000,PEG10000,OP-10 have stronger emulsifying ability to α-Al2O3 powder in ordinary condition and IW has more stability at 80~90°C. The optimum conditions are suggested as PEG6000 8g, IW 0.95g and ethanol 3mL per 50mL solution. Moreover, this composite electrolessplating solution is stable for seven days under 90°C. Therefore it has more dispersing ability. The SEM images show that the powder in the coating is homogeneous. The electroless plating coating consists of α-Al2O3 and amorphous Ni-P that will change into crystal Ni3P and Ni-base solid solution after heat treatment at 400°C for one hour, the α-Al2O3 powders are dispersed evenly in the nickel matrix.

CORROSION PROTECTION OF ELECTROLESS PLATING Ni-P INCLUDING TiN NANOPARTICLES FOR BIPOLAR PLATES OF PEMFCs

2018 ◽  
Vol 25 (02) ◽  
pp. 1850052 ◽  
Author(s):  
GAO PINGPING ◽  
OUYANG CHUN ◽  
XIE ZHIYONG ◽  
TAO TAO
Keyword(s):  
Corrosion Resistance ◽  
Surface Morphology ◽  
Electroless Plating ◽  
Shell Structure ◽  
Compact Surface ◽  
Proton Exchange ◽  
Core Shell ◽  
Tin Coating ◽  
Sem Images ◽  
Core Shell Structure

The Ni-P/TiN coating was used as bipolar plate by electroless plating on Ti. Surface morphology and phase structure of the coatings were characterized by SEM and XRD, respectively. Corrosion resistance of Ni-P and Ni-P/TiN coating was measured in the simulated solution of Proton exchange membrane fuel cells (PEMFCs). The interfacial contact resistance (ICR) was conducted by applied different forces. SEM images indicated that the particles of core–shell structure were formed on the surface of coating on Ti substrate. The core–shell structure was composed of TiN core and Ni-P electroless plating shell. Compared with Ni-P coatings, the Ni-P/TiN coating showed better corrosion resistance behaviors and low ICR (below 10[Formula: see text]m[Formula: see text][Formula: see text] cm[Formula: see text] under pressure of 200 N/cm[Formula: see text]. TiN particles and distribution of core–shell were in favor of the formation of coating and compact surface morphology. The good conductivity was attributed to the compact surface morphology of coating. The Ni-P/TiN coating showed excellent interfacial conductivity and good corrosion resistance at applied high potential in simulated solution of PEMFCs.

The Photoluminescence Enhancement and Stability of Porous Silicon by Cathodic Reduction and Acid Treatment

2014 ◽  
Vol 887-888 ◽  
pp. 458-461
Author(s):  
Chang Qing Li ◽  
Kun Wang ◽  
Pei Jia Liu ◽  
Qi Ming
Keyword(s):  
Electron Microscope ◽  
Porous Silicon ◽  
Acid Treatment ◽  
Cathodic Reduction ◽  
Luminescence Properties ◽  
Sem Images ◽  
Photoluminescence Enhancement ◽  
The Stability ◽  
Scanning Electron ◽  
Cathode Reduction

Porous silicon (PSi) was fabricated by using electrochemical anodic etching method. Then acid treatment and cathode reduction treatment were employed to improve the luminescence properties and stability of PSi material. Photoluminescence (PL) measurements and scanning electron microscope (SEM) were used to observe the luminescence properties and microstructure of samples, respectively. The results of PL measurements showed that the PL intensity and the stability of luminescence of samples after cathodic reduction and acid treatment were significantly improved. The SEM images showed that the porosity of PSi may be increased through the cathodic reduction treated.

scholarly journals The influence of the nature and textural properties of different supports on the thermal behavior of Keggin type heteropolyacids

2006 ◽  
Vol 71 (3) ◽  
pp. 235-249 ◽  
Author(s):  
Alexandru Popa ◽  
Viorel Sasca ◽  
Mircea Stefanescu ◽  
Erne Kis ◽  
Radmila Marinkovic-Neducin
Keyword(s):  
Thermal Stability ◽  
Thermal Decomposition ◽  
Thermal Behavior ◽  
Solid Phase ◽  
Textural Properties ◽  
Nitrogen Adsorption ◽  
Active Phase ◽  
Support Surface ◽  
Sem Images ◽  
The Stability

In order to obtain highly dispersed heteropolyacids (HPAs) species, H3PMo12O40 and H4PVMo11O40 were supported on various supports: silica (Aerosil - Degussa and Romsil types) and TiO2. The structure and thermal decomposition of supported and unsupported HPAs were followed by different techniques (TGA-DTA, FTIR, XRD, low temperature nitrogen adsorption, scanning electron microscopy). All the supported HPAs were prepared by impregnation using the incipient wetness technique with a 1:1 mixture of water-ethanol. Samples were prepared with different concentrations to examine the effect of loading on the thermal behavior of the supported acid catalysts. The thermal stability was evaluated with reference to the bulk solid acids and mechanical mixtures. After deposition on silica types supports, an important decrease in thermal stability was observed on the Romsil types and a small decrease on the Aerosil type. The stability of the heteropolyacids supported on titania increased due to an anion-support interaction, as the thermal decomposition proceeded in two steps. The structure of the HPAs was not totally destroyed at 450 ?C as some IR bands were still preserved. A relatively uniform distribution of HPAs on the support surface was observed for all compositions of the active phase. No separate crystallites of solid phase HPAs were found in the SEM images.

scholarly journals Effect of Modified Kiln Dust and a Cationic Surfactant on the Removal of Aromatic and Heavy Metal Compounds from Fuels

2019 ◽  
Vol 35 (5) ◽  
pp. 1508-1513
Author(s):  
Noura Yahya El Mehbad
Keyword(s):  
Heavy Metals ◽  
Cationic Surfactant ◽  
Oil Quality ◽  
Cement Kiln ◽  
Polar Molecules ◽  
Optimum Conditions ◽  
Metal Compounds ◽  
Before And After ◽  
The Stability ◽  
Kiln Dust

This paper aims to investigate removal of aromatic and heavy metals compounds from fuels using cement kiln dust, and a cationic surfactant. The effect of a cationic surfactant and the composition of kiln dust on the stability of fuel was studied. The optimum conditions of adsorption were investigated. The stability of fuels was improved after adsorption because of the absorption of heavy metals, which act as catalysts. The concentrations of kiln dust and additives are effective for the absorption of heteroatoms of polar and nonpolar molecules. The addition of different concentrations of the cationic surfactant to kiln dust enhances the removal of polar molecules in fuel. The relation between the efficiency of the cationic surfactant and the enhanced removal of polar molecules was established. This study suggests a new mechanism to remove polar molecules according to the structure of the additive. Several parameters that affect the performance of the removal process were investigated under all optimum conditions. A complete chemical analysis of the fuels before and after treatment was performed, and the stability of the fuel was evaluated at different conditions. The prepared additive could enhance the oil quality and is environmentally safe. The adsorption behaviour of kiln dust was investigated to find a new mechanism of its efficiency. The results confirm the role of the cationic surfactant in the purification of fuels and the effectiveness of kiln dust in improving the stability of fuels, which depend on the concentration of the cationic surfactant and the nature of the kiln dust.

Preparation of Pd /α–Al2O3 and Pd-Ag/α–Al2O3 Membranes by Electroless Plating and Permeation Measurements

2012 ◽  
Vol 1372 ◽  
Author(s):  
L. Ortiz-Martínez ◽  
M. Torres-Rodríguez ◽  
M. Gutiérrez-Arzaluz
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Electroless Plating ◽  
Energy Dispersive Spectroscopy ◽  
Ceramic Composite ◽  
Composite Membranes ◽  
X Ray Diffraction ◽  
X Ray ◽  
Α Al2o3 ◽  
Scanning Electron

ABSTRACTIn this work, the synthesis of dense Pd/α–Al2O3 and Pd-Ag/α–Al2O3 ceramic composite membranes was done through the sequential electroless plating technique of Pd and Ag. The precursors are solutions of PdCl2 and AgNO3 and N2H4 salts, as reducing agent. The membranes were characterized by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Energy Dispersive Spectroscopy (EDS). The permeation tests of H2 and N2 was carried out at 20 psi of pressure and at 25°C, resulted πH2=5.2x10-9 mol H2/m2·s·Pa and πN2=8.2x10-10 mol N2/m2·s·Pa.

scholarly journals Biodegradation and Biosurfactant Production by Agrobacterium tumefaciens Utilizing Weathered Mineral base Oil

2012 ◽  
Vol 6 (1) ◽  
pp. 45-55
Author(s):  
Reem Waleed Yonis
Keyword(s):  
Agrobacterium Tumefaciens ◽  
Room Temperature ◽  
Biosurfactant Production ◽  
Production Medium ◽  
Optimum Conditions ◽  
Base Oil ◽  
Initial Concentration ◽  
Weathered Oil ◽  
The Stability ◽  
Mineral Base

ptimum condition of biodegradation and biosurfactant production from spilled weathered base oil by Agrobacterium tumefaciens was studied in batch culture. Results showed that the optimum conditions for biosurfactant production was at pH7, temperature 30°C, incubation period 72h, and addition of weathered oil in a concentration of 3%, which yielded high biosurfactant production reached 6.6 g/l. The results also showed capability of isolate to degrade 70% of initial concentration of weathered oil 3%. Some characteristics and nature of produced biosurfactant was studied, the results showed that the biosurfactant is white to yellow in color, and viscous at room temperature, and needs little heating to be prepared in aqueous solution, insoluble in water and some organic solvents. The results also indicated higher stability of produced biosurfactant at neutral pH, and the stability decreased at pH less than 5 and up to 9, while the best stability of produced biosurfactant was at 30 and 40˚C. The addition of crude biosurfactant in concentration 20mg/l to the production medium lead to stimulate the isolate for uptake of weathered oil and increase biosurfactant production, while the biomass production did not affected significantly.

Effect of Electroless Plating Conditions on Toluene Catalytic Combustion Performance of Palladium-Based Catalyst

2011 ◽  
Vol 233-235 ◽  
pp. 416-419
Author(s):  
Yong Feng Li ◽  
Yu Li ◽  
Rong Jian Mai ◽  
Qian Yu ◽  
Lin Yu
Keyword(s):  
Electroless Plating ◽  
Catalytic Combustion ◽  
Bath Temperature ◽  
Catalytic Performance ◽  
Plating Bath ◽  
High Efficient ◽  
Plating Method ◽  
Catalytic Stability ◽  
The Stability ◽  
Palladium Salt

Catalytic combustion of volatile organic compounds (VOCs) is a high efficient and low-polluted technique. In this paper, the palladium-based combustion catalysts on cordierite honeycomb ceramics (CHC) substrate without interlayer film — Pd/CHC, were prepared by electroless plating method, and the effect of preparing conditions for the catalysts on the catalytic performance of toluene combustion was mainly studied. The optimal conditions were confirmed as follows: plating bath temperature is 60°C, plating time is 30min, palladium salt concentrationis 0.2g/L, and calcination temperature after plating is 500°C. Finally, the stability test further indicated that the Pd/CHC catalyst prepared by the optimal electroless plating conditions has good catalytic stability.

scholarly journals Purification and modification of neem gum for enhancement of its suspending property

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Mohan G. Kalaskar ◽  
Rakesh E. Mutha ◽  
Anilkumar U. Tatiya ◽  
Sandip D. Firke ◽  
Sanjay J. Surana ◽  
...  
Keyword(s):  
Calcium Chloride ◽  
Stability Study ◽  
Sodium Carboxymethylcellulose ◽  
Cross Link ◽  
Physiochemical Properties ◽  
Suspension Formulation ◽  
Sedimentation Volume ◽  
The Stability ◽  
Suspending Agents ◽  
Dispersing Ability

Abstract Background The present study aimed to purify and modify the neem gum (NG) to evaluate its dispersing ability in a pharmaceutical suspension formulation. The modification was carried out to cross-link the sugars as carbamate in the presence of calcium chloride to improve the suspending property. Physiochemical properties such as pH, solubility, swelling index and ash value were performed before investigating the dispersing potential. The suspending potential of neem gum was studied in its different forms such as purified and modified gum in paracetamol suspension and was compared with sodium carboxymethylcellulose (CMC) being used as standard at a concentration range of 0.25–1% (w/v). The test suspensions were evaluated for the redispersibility, flowability, sedimentation volume (%) and stability study for 3 months. Result The redispersibility of modified neem gum (MNG) was found equal to CMC at a higher concentration. The flowability and apparent sedimentation of test suspending agents and CMC were found in the order of NG > MNG > CMC. It showed a positive correlation with the viscosity of suspension formulations. All the test paracetamol suspension formulations were found stable in the stability study. Conclusion The findings of the present study showed that as an alternate suspending agent, modified cross-linked neem gum could be used.

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