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Total dissolved solids ( TDS) is a measure of the dissolved combined content of all inorganic and organic substances present in a liquid in molecular, ionized, or micro-granular ( colloidal sol) suspended form. TDS are often measured in parts per million (ppm). TDS in water can be measured using a digital meter.
Thermogravimetric analysis or thermal gravimetric analysis (TGA) is a method of thermal analysis in which the mass of a sample is measured over time as the temperature changes. . This measurement provides information about physical phenomena, such as phase transitions, absorption, adsorption and desorption; as well as chemical phenomena including chemisorptions, thermal decomposition, and ...
Temperature programmed desorption (TPD) is the method of observing desorbed molecules from a surface when the surface temperature is increased. When experiments are performed using well-defined surfaces of single-crystalline samples in a continuously pumped ultra-high vacuum (UHV) chamber, then this experimental technique is often also referred to as thermal desorption spectroscopy or thermal ...
Sodium hexametaphosphate ( SHMP) is a salt of composition Na6[ (PO3)6]. [3] Sodium hexametaphosphate of commerce is typically a mixture of metaphosphates (empirical formula: NaPO 3 ), of which the hexamer is one, and is usually the compound referred to by this name. Such a mixture is more correctly termed sodium polymetaphosphate.
The structure of solid hydrazine was determined by X-ray diffraction. In this phase the N-N bond has a length of 1.46 Å and the nearest non-bonded distances are 3.19, 3.25 and 3.30 Å. Synthesis and production. Diverse synthetic pathways for hydrazine production have been developed. The key step is the creation of the N–N single bond. The ...
Analytical thermal desorption. Analytical thermal desorption, known within the analytical chemistry community simply as "thermal desorption" (TD), is a technique that concentrates volatile organic compounds (VOCs) in gas streams prior to injection into a gas chromatograph (GC). It can be used to lower the detection limits of GC methods, and can ...
Naphthalene is the most abundant single component of coal tar. The composition of coal tar varies with coal type and processing, but typical coal tar is about 10% naphthalene by weight. In industrial practice, distillation of coal tar yields an oil containing about 50% naphthalene, along with twelve other aromatic compounds.
In environmental chemistry, the chemical oxygen demand ( COD) is an indicative measure of the amount of oxygen that can be consumed by reactions in a measured solution. It is commonly expressed in mass of oxygen consumed over volume of solution which in SI units is milligrams per litre ( mg / L ). A COD test can be used to easily quantify the ...