Beryllium General Characteristics According to Hornbostel (1991), Beryllium is a hard, exceptionally, lightweight, gray-white metal, corrosion resistant at ordinary temperatures; chemically it is related to aluminum. Other than titanium, it is the only light metal which has both good strength and a high melting point. Additionally, it is a good electrical conductor, has high modulus of elasticity, exceptionally transmit x-rays and sounds at very high velocities. Moreover, it has the ability to…
goal of the OMCVD process, to produce zero-valent state of metal element with existing technology and producing units is only possible for the Ni(CO)4. The processes which apply other precursors usually produce the thin film of metal polluted by the carbon or…
not rust or stain like normal steel would and even though it is called stainless steel, it is not entirely stainless, because in low-oxygen, high salinity environments it is able to be stained. The main difference between stainless steel and general carbon steel is the amount of chromium present. Due to the amount of chromium that stainless steel contains, the stainless steel will form a chromium oxide film which will help prevent corrosion as it blocks the oxygen fusing to the surface of the…
alloy and Iron is an element. Steel is also called as an alloy of iron, with the content of carbon controlled. 4% of carbon in Iron makes it Cast Iron and when the carbon content is less than 2%, the product is steel. Cast Iron is made from pig iron, which is the by-product of smelting of iron from an iron-foundry. Mild steel, which is also known as plain carbon steel, approximately contains 0.05-0.15% of carbon. This makes it malleable and ductile. Mild steel has a relatively low tensile…
Introduction 1.1 Polyurethane polyurethanes were first developed by Otto Bayer and coworkers in 1937. Shortly thereafter, Schollenberger and coworkers used formula modification to prepare elastomeric polyurethane products from Bayer's products that were like nylon or other engineering plastics in physical characteristics. PUs are widely used in coatings, flexible and rigid foams, elastomers, and composites. Reasons for the use of polyurethane coatings include: high performance characteristics…
Diels-Alder Reaction Objective: The objective of this lab was to do a diels-alder reaction using anthracene, maleic anhydride, and xylene to create 9,10-dihydroanthracene, 10-, -succinic acid anhydride. Experimental: Anthracene (1.00g, 5.61x 10-3 mol), maleic anhydride (0.75g, 7.61x 10-3 mol), xylene (5mL, 4.71x 10-2 mol), and a stir rod were added into a round-bottomed flask. The round-bottom flask was then moved to the hood where the it was attached to a distillation column, placed on…
staggered conformation,dihedral angle and a few more. Eclipsed conformation is the conformation whereby the C-H bonds on one carbon is directly aligned with the C-H bonds of the adjacent carbon. When the C-H bond of one carbon bisects the H-C-H bond on the adjacent carbon, it is known as staggered conformation. Dihedral angle is the angle which separates the the bond on carbon atom from another bond of the adjacent atom. The conformer is each possible structure of the isomerism. Conformational…
6.3. A. Microemulsions (135-143) Microemulsions are clear, stable, isotropic mixtures of oil, water, and surfactant, frequently in combination with a cosurfactant 135-137. Microemulsions have several advantages such as enhanced drug solubility, good thermodynamic stability, and higher transdermal permeability over conventional formulations 138,139. Many studies reported the use of microemulsions as topical drug delivery vehicles showed their ability to improve transdermal and dermal delivery…
Lubczak R (2013) Polyester resins with carbazole ring. Polymer Intern 62; 1243-1249. Doi: http://dx.doi.org/10.1002/pi.4415 18. “Epoxide resins. Method of testing. Determination of the epoxide number and epoxide equivalent”, Polish Standards PN-C-89085-13:1987, Ed. Polish Committee for Standardization, 1987. 19. Kijowska D (2005) Alkylene carbonates with the five-membered ring. Preparation, properties and applications “ Przemysł Chemiczny, 84;…
In pursuit of our continued interest in the development of solvent-free and green synthetic procedures, we decided to explore the use of tartaric acid catalyst for synthesis of polysubstituted quinolines via Friedlander condensation in high to excellent yields at 70 °C under solvent-free conditions. Initially the reaction between 2-aminobenzophenone (1.0 mmol) and dimedone (1.0 mmol), as the model reaction was examined in the presence varying amount of tartaric acid as catalyst and the results…