Electroless nickel (EN) plating was discovered by Brenner & Riddell in 1946. (1) EN plating is being large economically accessible under 30 years, is generally youthful compared with other plating. However, it has obtained significant industrial importance, being the most vital catalytic process in use today with a development rate of 5% annually. (2) Electroless nickel plating is a process in which one or more layers of nickel is deposited onto an active substrate by chemical reduction without the utilization of an external power source. (3) The process is termed “electroless” in light of the fact that the electrons are supplied by a chemical reducing agent instead of electrically. (2) Since the metal being applied is in the solution and adheres itself to the substrate without the utilization of an electric current, it is also referred to as an “autocatalytic” process. (3) A base substrate being plated also catalytic in nature or a substrate catalyzed by some form of pretreatment. The specific catalytic surfaces (almost all metals of Group …show more content…
It functions as to provide for a moderate rate of reaction of nickel precipitation and to prevent precipitation of the nickel compound. The complexing agents generally further solubilize the hypophosphite degradation product formed during the plating process and to complex the nickel ions present in the solution. The complexing agents form a more stable nickel complex with nickel ions and slow down directly the precipitation of nickel ions from the plating solution as insoluble salts such as phosphites. Complexing agents may also act as catalyst inhibitors to reduce the potential for spontaneous decomposition of the electroless nickel plating bath. Complexing agents used in electroless nickel plating includes carboxylic acids, polyamine or sulfonic acids or a mixture of them. The complexing agents normally are used at concentration about 20 to about 40 g/L.
In this case, the nitrate ion moved from one compound to another as the Cu was replaced by Zn. The zinc dissolved to form zinc (II) ions as the copper (II) ions came out of the solution as copper metal and deposited on the surface of the
The phrase “you never know what someone is really going through until you walk in their shoes,” is something Barbara Ehrenreich took seriously. A writer who had a Ph.D. in biology decided to give up her whole life to research poverty in America. Yet, her research was a little different than most. Instead of interviewing different workers in the lower class she joined them and attempted to live on minimum wage. The way she researched this type of life gives a whole new look into what the lower class actually has to go through.
The substrate coated catalyst can be used multiple times based on the exposure conditions and hence reusable (NAIR & (IN), 2012).
According to recent statistics, zinc is the third most commonly used nonferrous metal in the United States. This unassuming metal was among the first minerals exploited by Man, used as a decorative material for thousands of years, although it never achieved the fame and notoriety of other metals such as gold or silver. In more recent times, new extraction and processing methods have allowed Man to produce higher-quality zinc than ever before, and to use it in an astonishingly high number of chemical and high-tech applications.
Catalyst support must have a certain properties in order to enhance the catalytic activity. Thus in order to choose the most suitable support material it must have the certain physical and chemical properties. Among the properties are the catalyst support must be stable under reaction and regeneration condition, have high porosity for the mass and heat transport to be efficient and allow easy diffusion in and out , possess large surface area to increase the activity and distribution of the active components, ability to sustain and retain mechanical stability at high temperatures to prevent abrasion and increase durability of the catalyst on the support, possess high heat capacity and thermal conductivity in order to prevent the heat of adsorption igniting the powdered metal, and must be inert but reactive material.
Iqbal, M. K. (2013, March 27). NED University of Engineering and Technology. Retrieved from Department of Metallurgy Engineering: http://www.neduet.edu.pk/myd/TE/MY%20302.pdf
The book “Nickel and Dimed” is a very thought provoking read. Dr. Ehrenreich begins her book with the introduction by discussing with the audience how she developed the idea for this book during an expensive lunch. Dr. Ehrenreich speculated how workers with such little skill and education survive on such inadequate incomes. She can not fathom how these people are surviving, and wants to find out and understand their “tricks”. Dr. Ehrenreich decides to consider an experiment where she examines the consequences of the welfare reform by going out and trying to work and survive in the low wage work environment all while living a low wage lifestyle. She also decides to make some rules for her experiment. The first rule is she can
Upon reading the first page, I knew I would like this book. The writing style is almost like a memoir; it’s in the first person from the perspective of Nomi Nickel. The first ten chapters give us a look into Nomi nickels past, her opinions, and thoughts. They show the transition of her thoughts from a straight edge Mennonite follower to a rebellious teenager. She has a dry sense of humor that is thrown into her everyday activities. It’s a surprise when it happens, like when the garbage men throw out Ray’s hutch, not only was that unexpected but Ray’s reaction was surprising. Many of the teens in the town represent a character foil. On Saturday nights they go out drinking, partying, having sex, and on Sunday they return to their strict religious
Mr. Cronstedt discovered nickel in a mineral called niccolite. He originally planned to extract copper from this new mineral but got none at all. This is why nickel, at first, was called "false copper". Instead, Cronstedt got a silvery-white metal, which was eventually used for other things.
Saturated sodium chloride solution, also known as brine solution, is used to wash the distillate mixture. The distillate mixture is the phosphoric acid the co-distilled with the product. The brine solution also removes most of the water from the 4-methylcyclohexane layer. When six drops of 4-methylcyclohexene were added with two
The objective of this experiment is to study the continuous variations method that is used to determine the composition of the solution Ni2+ ethylenediamine complexes.
Nickel and Dimed: On (Not) Getting By in America, published in 2001 by Barbara Ehrenreich, is a book about an author who goes undercover and examines lives of the working lower class by living and working in similar conditions. Ehrenreich sets out to learn how people survive off of minimum wage. For her experiment, she applies rules including that she cannot use skills acquired from her education or work during her job search. She also must take the highest-paying job offered to her and try her best to keep it. For her search of a home, she has to take the cheapest she can find. For the experiment, Ehrenreich took on low-wage jobs in three cities: in Florida, Maine, and Minnesota.
...mpositional control needed and also the reactivity of the titanium. Fatigue failure has been known to occur with nitinol because of the extreme amounts of fatigue strain that it is necessarily exposed to. This is because it is still not completely defined how durable nitinol is, so it cannot be known what to use it for as it is the best of all metals known in this case. So it is used for the highest demanding applications but in some cases it can’t handle the pressure sustained. Another use for nitinol is a temperature control system, which would work by changing shape can activate a variable resistor or switch which would control the temperature, this is a situation where it is very significant for nitinol to be a smart material otherwise this system would simply just not work. There are many others but they are not really relevant to the engineering industry.
Aluminum is one of a number of soft metals that scientists call "poor" metals. It can be shaped and twisted into any form. It can be rolled into thick plates for armored tanks or into thin foil for chewing gum wrappers. It may be drawn into a wire or made into cans. Aluminum is a generally popular metal because it does not rust and it resists wear from weather and chemicals. (Bowman, 391) Aluminum is an element. Its atomic number is thirteen and its atomic weight is usually twenty-seven. Pure aluminum melts at 660.2ºC and boils at 2500ºC. Its density is 2.7 grams per cube centimeter. Aluminum is never found uncombined in nature. (Bowman, 391) Aluminum is a very useful metal that is light, easy to shape and can be strong. This makes aluminum one of the most used metals in the world, right behind iron and steel. (Geary, 185) In its pure state, aluminum is quite weak compared to the other metals. However, its strength can be greatly increased by adding small amounts of alloying elements, heat-treating, or cold working. Only a small percentage of aluminum is used in its pure form. It is made into such items as electrical conductors, jewelry, and decorative trim for alliances and cars. A combination of the three techniques has produced aluminum alloys that, pound for pound, are stronger than structural steel. Some common metals used in alloys for aluminum are copper, magnesium and zinc.(Walker, 31) The added elements give the aluminum strength and other properties. (Newmark, 41) Aluminum is one of the lightest metals. It weighs about 168.5 pounds per cubic foot, about a third as much as steel which weighs 487 pounds per cubic foot. (Neely, 214) As a result, aluminum has replaced steel for many uses. For example, some ...
The cell anode is usually a piece of the metal to be plated from solution; this enables the anode reaction of metal dissolution to replace the metal ion lost from solution by the cathodic decomposition. Factors There are many various factors that affect the mass deposited during electroplating:- 1). Current (A) - An increase in the amount of current increases the amount of substance deposited in a fixed amount of time, because there is more energy available to move ions/electrons to the cathode from the anode. A smaller current will pump fewer copper ions from the anode to the cathode in the same amount of mass gained on the cathode is lower. 2).