scholarly journals Influence of Wetting Additive Based on C12 - C14 Alkyl Ester Sulphate with Essential Oils on the Quality of Nickel Coating

Author(s):  
Indira Šestan ◽  
Demira Bedak Ogri? ◽  
Amra Odobaši? ◽  
Amra Bratov?i? ◽  
Ema Obrali?

The influence of wetting additive based on C12 - C14 alkyl ester sulfate with essential oils on the quality of nickel coatings is examined in the paper. The additive was tested at different concentrations added to the base electrolyte, taking the following concentrations: the concentration recommended twice lower (C1); lower recommended concentration (C2); upper recommended concentration (C3); the concentration twice higher compared to the lower recommended (C4) and the concentration twice higher compared to the upper recommended (C5). The value of the surface tension of the solution was determined, and the corrosion resistance in the salt chamber was examined. In addition, what is important in the production itself is the visual appearance of the coating, which was determined using the Hull cell test. The additive has been proven to be effective in reducing the surface solutions, which directly affects the production of nickel coatings of better quality and aesthetic appearance.

Author(s):  
Sanjib Kundu ◽  
Prasanta Sahoo ◽  
Suman Kalyan Das

Electroless nickel coating is a novel method of coating which can be developed in various combinations of alloys and composites each having its unique set of characteristics. Electroless nickel coatings are mainly used for wear and corrosion resistant properties. However, additional characteristics like smoothness of deposit, low friction, descent plating rate, electrical and magnetic properties also make them suitable for a host of applications. The properties of electroless nickel coatings depend mainly on the electroless solution ingredients as well as deposition conditions. Important deposition parameters include bath temperature, concentration of nickel source, concentration of reducing agent, pH of the solution, concentration of surfactants, and so on. Moreover, heat treatment is found to modify the microstructure of the coating and influence certain properties viz. hardness, wear resistance, corrosion resistance, etc. A large number of works have been published by the researchers on the evaluation of electroless nickel coating performance on the basis of hardness, roughness, corrosion resistance, friction and wear resistance for various types of coatings and substrates. Several approaches are proposed in the literatures to solve the problems related with optimization of these parameters. It is felt that a review of the various approaches developed would help to compare their main features and their relative advantages or limitations which will enable to choose the most suitable approach for a particular application and also throw light on aspects that needs further attention. In this regard, the present paper presents a review on the developments done on the optimization of electroless nickel coatings to increase its efficiency.


2011 ◽  
Vol 105-107 ◽  
pp. 1666-1670 ◽  
Author(s):  
Yan Wang ◽  
Wen Ge ◽  
Qian Yang ◽  
Wen Cheng

With the purpose of decorative bright nickel plating process, nano-nickel and ordinary bright nickel coatings were prepared by applying the electro-deposition method with DC and PRC respectively. The grain sizes, organizational structures and surface morphologies of samples were characterizated by X-ray diffraction(XRD) and scanning electron microscopy (SEM) analysis. The corrosion resistance of the samples were determined by immersion corrosion test, salt spray corrosion test and electrochemical methods. The results showed that the corrosion resistance of reverse pulsed electrodeposition nano-nickel coating is superior to the DC electrodeposition nickel coating.


Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1196
Author(s):  
Antonio López-Gómez ◽  
María Ros-Chumillas ◽  
Alejandra Navarro-Martínez ◽  
Marta Barón ◽  
Laura Navarro-Segura ◽  
...  

The use of vapour of essential oils (EOs) through an innovative pilot-plant packaging device was studied to preserve the quality of sliced mushrooms during storage. A mix of EOs (eugenol, bergamot EO, and grapefruit EO) was vaporized (100 and 125 µL L−1) and applied during packaging of sliced mushrooms under modified atmosphere packaging (MAP); then, the product quality was studied during cold storage up to 12 days. The highest colour changes of EOs125 samples, which were observed in the mushroom stipe, were not observed with the EOs100 atmosphere. Thus, the high polyphenoloxidase activity observed in untreated samples after 5–7 days was highly controlled with the vapour EOs atmospheres. Furthermore, the visual appearance scores of EOs100 samples were still over the limit of usability, while untreated samples were already below this threshold after 5 days of storage. A strong bacteriostatic effect was achieved with vapour EOs, reducing the Pseudomonas spp. (the main microbial genus in cultivated mushrooms) growth by ≈1.7 log CFU g−1, regardless of the EOs dose, after 12 days. The activity of phenyl ammonia lyase was also reduced up to ≈0.4 enzymatic units with the EOs100 treatment. Conclusively, packaging of sliced mushrooms under an atmosphere enriched with 100 µL L−1 EOs vapour highly controlled the quality loss of sliced mushrooms owing to their enzymatic inhibition and high bacteriostatic effect.


Author(s):  
K. T. Tokuyasu

During the past investigations of immunoferritin localization of intracellular antigens in ultrathin frozen sections, we found that the degree of negative staining required to delineate u1trastructural details was often too dense for the recognition of ferritin particles. The quality of positive staining of ultrathin frozen sections, on the other hand, has generally been far inferior to that attainable in conventional plastic embedded sections, particularly in the definition of membranes. As we discussed before, a main cause of this difficulty seemed to be the vulnerability of frozen sections to the damaging effects of air-water surface tension at the time of drying of the sections.Indeed, we found that the quality of positive staining is greatly improved when positively stained frozen sections are protected against the effects of surface tension by embedding them in thin layers of mechanically stable materials at the time of drying (unpublished).


Author(s):  
Ashish Dwivedi ◽  
Nirupma Tiwari

Image enhancement (IE) is very important in the field where visual appearance of an image is the main. Image enhancement is the process of improving the image in such a way that the resulting or output image is more suitable than the original image for specific task. With the help of image enhancement process the quality of image can be improved to get good quality images so that they can be clear for human perception or for the further analysis done by machines.Image enhancement method enhances the quality, visual appearance, improves clarity of images, removes blurring and noise, increases contrast and reveals details. The aim of this paper is to study and determine limitations of the existing IE techniques. This paper will provide an overview of different IE techniques commonly used. We Applied DWT on original RGB image then we applied FHE (Fuzzy Histogram Equalization) after DWT we have done the wavelet shrinkage on Three bands (LH, HL, HH). After that we fuse the shrinkage image and FHE image together and we get the enhance image.


2014 ◽  
Vol 59 (1) ◽  
pp. 355-358
Author(s):  
M. Karaś ◽  
M. Nowak ◽  
M. Opyrchał ◽  
M. Bigaj ◽  
A. Najder

Abstract In this study, the effect of zinc interlayer on the adhesion of nickel coatings reinforced with micrometric Al2O3 particles was examined. Nickel coating was applied by electroplating on EN AW - 5754 aluminium alloy using Watts bath at a concentration of 150 g/l of nickel sulphate with the addition of 50 g/l of Al2O3. The influence of zinc intermediate coating deposited in single, double and triple layers on the adhesion of nickel coating to aluminium substrate was also studied. The adhesion was measured by the thermal shock technique in accordance with PN-EN ISO 2819. The microhardness of nickel coating before and after heat treatment was additionally tested. It was observed that the number of zinc interlayers applied does not significantly affect the adhesion of nickel which is determined by thermal shock. No defect that occurs after the test, such as delamination, blistering or peeling of the coating was registered. Microhardness of the nickel coatings depends on the heat treatment and the amount of zinc in the interlayer. For both single and double zinc interlayer, the microhardness of the nickel coating containing Al2O3 particles increased after heat treatment, but decreased when a triple zinc interlayer was applied.


2013 ◽  
Vol 18 (2-3) ◽  
pp. 33-41
Author(s):  
Dominik Sankowski ◽  
Marcin Bakala ◽  
Rafał Wojciechowski

Abstract The good quality of several manufactured components frequently depends on solidliquid interactions existing during processing. Nowadays, the research in material engineering focuses also on modern, automatic measurement methods of joining process properties, i.a. wetting force and surface tension, which allows for quantitative determination of above mentioned parameters. In the paper, the brazes’ dynamic properties in high-temperatures’ measurement methodology and the stand for automatic determination of braze’s properties, constructed and implmented within the research grant nr KBN N N519 441 839 - An integrated platform for automatic measurement of wettability and surface tension of solders at high temperatures, are widely described


2019 ◽  
Vol 70 (6) ◽  
pp. 2015-2020
Author(s):  
Silvia Robu ◽  
Aurelia Romila ◽  
Olimpia Dumitriu Buzia ◽  
Adrian Florin Spac ◽  
Camelia Diaconu ◽  
...  

Numerous articles on Salvia officinalis L. have been published regarding the composition of their essential oil. The considerable variation found may be due to the quality of the plant material as well as to the methods used for analysis. A simple GC-MS method was developed and optimized in the QbD approach, for the determination of sage essential oils. The optimization of GC-MS analysis was performed using different mobile phase flows, injection volumes, split ratios and temperature programs. The optimized method proved to be simple and can be successfully applied for the determination of sage essential oils.


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