Magnetic conventional synthesis

One of such unique coatings is Diamond Like Carbon (DLC). The conventional synthesis of synthetic diamonds requires extremely high temperatures and pressures. By PECVD, Diamond Like Carbon is created under mild conditions by the decomposition of methane in H2/CH4 mixture. The applications of DLC are numerous coatings for cutting tools, optical fibres, electronic devices for reading magnetic tapes, or even protective coatings in chemical reactors. 

Supercritical fluids (SCFs) offer the potential for a controlled solution environment because of the tunability of their properties by small changes in temperature and pressure. Indeed, near-critical water and supercritical water are obvious candidates as solvents in nanoparticle formation because water is the most commonly used solvent in conventional synthesis of inorganic particles. However, other solvents, such as carbon dioxide, can also be used. Several methods that take advantage of SCF behavior are described below. Not all have been employed in the production of magnetic nanoparticles. However, they represent a natural bridge between methods that are carried out mainly in the liquid state and those that are carried out in the gaseous state. 

Conventional synthesis of magnetic nanoparticles, well described in the scientific literature, includes a variety of thermal decomposition and solvothermal methods and a number of coprecipitation reactions [3-5]. Although these methods yield high-quality magnetic materials, many exhibit drawbacks associated with extreme reaction conditions. The controlled low-temperature... 

In this article, we describe and summarize our studies on the structural, magnetic,and transport properties of buckytubes. In addition, we describe how a conventional arc discharge can be modified into a stable glow discharge for the efficient synthesis of well-aligned buckytubes. 

Certain of the p-chlorophenyl-substituted carboxylic acids are related products in a multistep synthesis. A schematic outline of synthetic procedures is presented to clarify these relationships. Properties of seven new p-chlorophenyl-substituted intermediates and six new p-chlorophenyl-substituted carboxylic acids are reported. All of the 13 new compounds have been characterized by conventional criteria. Both gas-liquid chromatography and nuclear magnetic resonance are used to assess the purity of the carboxylic acids and their intermediates. 

Ferrite ceramics have found widespread applications as materials for permanent magnets and recording media due to their low cost and attractive magnetic properties. The conventional method for manufacturing ferrite ceramics involves solid state reaction of oxide or carbonate precursors at high temperature. Although technically simple, this method does not readily allow control of the product s microstructure and purity, which is necessary for the attainment of optimal magnetic properties. As a result, there has been considerable research into the development of alternative synthesis techniques. 

Conventional microwave ovens are used less often for microwave chemistry today. Microwave reactors for chemical synthesis are commercially available and widely used in academia and in industry. These instruments have built-in magnetic stirring, direct temperature control of the reaction mixture, shielded thermocouples or IR sensors, and the ability to control temperature and pressure by regulating microwave output power. 

Some of the problems seen with the commercially available polyimides such as limited shelf life,gelation and high ionic contamination are traceable to the raw materials themselves. A zone refining technique has been perfected for use with organic materials and these precursors have been used to synthesize ultrapure polyamic acids for IC device applications. The key feature of the synthesis is the use of solid ingots of the dianhydrides. Materials prepared by this technique show low metallic impurities and have been shown to be excellent film formers for a variety of applications. In particular a polyimide derived from PMDA-ODA has been used to passivate magnetic bubble devices. IR techniques coupled with electrical measurements have been used to optimize the cure conditions and a simple resist process has been defined to passivate these devices. Device performance compares well with conventional inorganic insulators. 

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