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Electroless Nickel Plating
Electroless Deposition, Electroless nickel-phosphorus plating, also referred to as ''E-nickel'', is a chemical engineering, chemical process that deposits an even layer of nickel-phosphorus alloy on the surface of a solid substrate, like metal or plastic. The process involves dipping the substrate in a water solution containing nickel salt (chemistry), salt and a phosphorus-containing reducing agent, usually a hypophosphite salt. It is the most common version of electroless nickel plating (EN plating) and is often referred by that name. A Electroless nickel-boron plating, similar process uses a borohydride reducing agent, yielding a nickel-boron coating instead. Unlike electroplating, processes in general do not require passing an electric current through the bath and the substrate; the redox reaction, reduction of the metal cations in solution to metallic is achieved by purely chemical means, through an autocatalysis, autocatalytic reaction. This creates an even layer of met ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autocatalysis
In chemistry, a chemical reaction is said to be autocatalytic if one of the reaction products is also a catalyst for the same reaction. Many forms of autocatalysis are recognized.Steinfeld J.I., Francisco J.S. and Hase W.L. ''Chemical Kinetics and Dynamics'' (2nd ed., Prentice-Hall 1999) pp. 151–2 A ''set'' of chemical reactions can be said to be "collectively autocatalytic" if a number of those reactions produce, as reaction products, catalysts for enough of the other reactions that the entire set of chemical reactions is self-sustaining given an input of energy and food molecules (see autocatalytic set). Examples Acid-catalyzed hydrolysis of esters produces carboxylic acids that also catalyze the same reaction. Indeed, the observation of an accelerating hydrolysis of gamma valerolactone to gamma-hydroxyvaleric acid led to the introduction of the concept of autocatalysis in 1890. The oxidation of hydrocarbons by air or oxygen is the basis of autoxidation. Like many radic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anode
An anode usually is an electrode of a polarized electrical device through which conventional current enters the device. This contrasts with a cathode, which is usually an electrode of the device through which conventional current leaves the device. A common mnemonic is ACID, for "anode current into device". The direction of conventional current (the flow of positive charges) in a circuit is opposite to the direction of electron flow, so (negatively charged) electrons flow from the anode of a galvanic cell, into an outside or external circuit connected to the cell. For example, the end of a household battery marked with a "+" is the cathode (while discharging). In both a galvanic cell and an electrolytic cell, the anode is the electrode at which the oxidation reaction occurs. In a galvanic cell the anode is the wire or plate having excess negative charge as a result of the oxidation reaction. In an electrolytic cell, the anode is the wire or plate upon which excess positive charge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Bureau Of Standards
The National Institute of Standards and Technology (NIST) is an agency of the United States Department of Commerce whose mission is to promote American innovation and industrial competitiveness. NIST's activities are organized into physical science laboratory programs that include nanoscale science and technology, engineering, information technology, neutron research, material measurement, and physical measurement. From 1901 to 1988, the agency was named the National Bureau of Standards. History Background The Articles of Confederation, ratified by the colonies in 1781, provided: The United States in Congress assembled shall also have the sole and exclusive right and power of regulating the alloy and value of coin struck by their own authority, or by that of the respective states—fixing the standards of weights and measures throughout the United States. Article 1, section 8, of the Constitution of the United States, ratified in 1789, granted these powers to the new Con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grace E
Grace may refer to: Places United States * Grace, Idaho, a city * Grace (CTA station), Chicago Transit Authority's Howard Line, Illinois * Little Goose Creek (Kentucky), location of Grace post office * Grace, Carroll County, Missouri, an unincorporated community * Grace, Laclede County, Missouri, an unincorporated community * Grace, Mississippi, an unincorporated community * Grace, Montana, an unincorporated community * Grace, Hampshire County, West Virginia * Grace, Roane County, West Virginia Elsewhere * Grace (lunar crater), on the Moon * Grace, a crater on Venus People with the name * Grace (given name), a feminine name, including a list of people and fictional characters * Grace (surname), a surname, including a list of people with the name Religion Theory and practice * Grace (prayer), a prayer of thanksgiving said before or after a meal * Divine grace, a theological term present in many religions * Grace in Christianity, the benevolence shown by God toward ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abner Brenner
In the Hebrew Bible, Abner ( ) was the cousin of Saul the King, King Saul and the commander-in-chief of his army. His name also appears as "Abiner son of List of minor Hebrew Bible figures, L–Z#Ner, Ner", where the longer form Abiner means "my father is Ner". Biblical narrative Abner is initially mentioned incidentally in Saul's history, first appearing as the son of Ner, Saul's uncle, and the commander of Saul's army. He then comes to the story again as the commander who introduced David to Saul following David's killing of Goliath. He is not mentioned in the account of the disastrous battle of Gilboa when Saul's power was crushed. Seizing the youngest but only surviving of Saul's sons, Ish-bosheth, also called Eshbaal, Abner set him up as king over Kingdom of Israel (united monarchy), Israel at Mahanaim, east of the Jordan River, Jordan. David (biblical king), David, who was accepted as king by Kingdom of Judah, Judah alone, was meanwhile reigning at Hebron, and for some ti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
François Auguste Roux
François () is a French language, French masculine given name and surname, equivalent to the English name Francis (given name), Francis. People with the given name * François Amoudruz (1926–2020), French resistance fighter * Voltaire, François-Marie Arouet (better known as Voltaire; 1694–1778), French Enlightenment writer, historian, and philosopher * François Beauchemin (born 1980), Canadian ice hockey player for the Anaheim Ducks * François Blanc (1806–1877), French entrepreneur and operator of casinos * François Bonlieu (1937–1973), French alpine skier * François Cevert (1944–1973), French racing driver * François Chau (born 1959), Cambodian American actor * François Clemmons (born 1945), American singer and actor * François Corbier (1944–2018), French television presenter and songwriter * François Coty (1874–1934), French perfumer * François Coulomb the Elder (1654–1717), French naval architect * François Coulomb the Younger (1691–1751), French ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charles Adolphe Wurtz
Charles Adolphe Wurtz (; 26 November 181710 May 1884) was an Alsatian French chemist. He is best remembered for his decades-long advocacy for the atomic theory and for ideas about the structures of chemical compounds, against the skeptical opinions of chemists such as Marcellin Berthelot and Henri Étienne Sainte-Claire Deville. He is well known by organic chemists for the Wurtz reaction, to form carbon-carbon bonds by reacting alkyl halides with sodium, and for his discoveries of ethylamine, ethylene glycol, and the aldol reaction. Wurtz was also an influential writer and educator. Life Adolphe Wurtz (he never used the name "Charles") was born in Strasbourg, where his father, Johann Jacob (Jean Jacques) Wurtz, was a Lutheran pastor in the nearby town of Wolfisheim. His wife, Adolphe's mother, Sophie Kreiss, died in 1878. When he left the Protestant gymnasium at Strasbourg in 1834, his father allowed him to study medicine as next best to theology. He devoted himself spe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suspension (chemistry)
In chemistry, a suspension is a heterogeneous mixture of a fluid that contains solid particles sufficiently large for sedimentation. The particles may be visible to the naked eye, usually must be larger than one micrometer, and will eventually settle, although the mixture is only classified as a suspension when and while the particles have not settled out. Properties A suspension is a heterogeneous mixture in which the solid particles do not dissolve, but get suspended throughout the bulk of the solvent, left floating around freely in the medium. The internal phase (solid) is dispersed throughout the external phase (fluid) through mechanical agitation, with the use of certain excipients or suspending agents. An example of a suspension would be sand in water. The suspended particles are visible under a microscope and will settle over time if left undisturbed. This distinguishes a suspension from a colloid, in which the colloid particles are smaller and do not settle. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Composite Material
A composite or composite material (also composition material) is a material which is produced from two or more constituent materials. These constituent materials have notably dissimilar chemical or physical properties and are merged to create a material with properties unlike the individual elements. Within the finished structure, the individual elements remain separate and distinct, distinguishing composites from mixtures and solid solutions. Composite materials with more than one distinct layer are called ''composite laminates''. Typical engineered composite materials are made up of a binding agent forming the ''matrix'' and a Filler (materials), filler material (particulates or fibres) giving ''substance'', e.g.: * Concrete, reinforced concrete and masonry with cement, lime or Mortar (masonry), mortar (which is itself a composite material) as a binder * Composite wood such as glulam and plywood with wood glue as a binder * Reinforced plastics, such as fiberglass and fibre-rein ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
