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Terms and Definitions
Published in Rick Houghton, William Bennett, Emergency Characterization of Unknown Materials, 2020
Rick Houghton, William Bennett
Relative density, or specific gravity, is a ratio of the weight of a solid or liquid to the weight of an equal volume of water and is used to describe buoyancy of a material. Water is used as the standard and is given a value of 1. Something with a relative density greater than 1 will sink in water; less than 1 will float. For example, mercury has a relative density of 13.6 and would sink in water, because it is 13.6 times heavier than an equal volume of water. Motor oil has a relative density of about 0.87 and would float on water (Figure 1.7).
Tribo-material Properties
Published in Ahmed Abdelbary, Extreme Tribology, 2020
Specific gravity (S), on the other hand, is a measure of the relative density of a substance as compared to the density of water at a standard temperature. The importance of this property arises when using grease as a lubricant. The grease requirement is often specified in grams, while grease dispensers are usually calibrated in cubic centimeters. Thus, we use the specific gravity to convert the units of weight to the units of volume. In the petroleum industry, an API (American Petroleum Institute) unit, which is a derivative of the conventional specific gravity, is used. The API scale is expressed in degrees which, in some cases, are more convenient to use than the specific gravity reading (Stachowiak and Batchelor, 1993). The API degree can be calculated according to the following empirical formula (O’Connor et al., 1968): () API=(141.5/S)−131.5
Crude Properties
Published in Mark J. Kaiser, Arno de Klerk, James H. Gary, Glenn E. Hwerk, Petroleum Refining, 2019
Mark J. Kaiser, Arno de Klerk, James H. Gary, Glenn E. Hwerk
For the Bayou Choctaw and West Hackberry crude blends, distillation was performed in accord with ASTM D2892 and the residuum was distilled at a pressure of 0.13 kPa using ASTM D5236 (U.S. DOE 2008). Distillation is on a mass percent basis with volume percent calculated using the specific gravity of the fractions (Figures 14.1 and 14.2). There are different approaches to crude oil assays and these are generally dependent on the purpose of the analysis. Crude quality is assessed by measuring physical properties such as relative density, refractive index or viscosity, or by empirical tests such as pour point or oxidation stability. Bulk property techniques, however, do not give any information on the molecular level.
Offshore oil and gas records circa 2020
Published in Ships and Offshore Structures, 2022
Crude oils are best understood in reference to one another and the best single diagram illustrating crude quality is a plot of crude API gravity versus sulfur content (Figure 4). Relative density (better known as specific gravity) is the density of crude relative to the density of water, both measured at the same temperature (60/60F). API gravity is related to specific gravity through a formula that expands the measurement scale and is described in degrees: Light crude oil is often defined as having API gravity between 35° and 50° API and heavy7 oil with API < 25°, although these cutoffs are by no means universal and other thresholds may be applied. Condensate or ultra-light crude is defined by API > 50°. Sulfur is the most common impurity in crude oil and crudes with sulfur content less than or equal to 0.5%wt are labelled sweet and those with greater than 1%wt sulfur are labelled sour, with the intermediate category labelled medium or medium-sour (Kaiser, de Klerk, et al. 2020).
Synthesis of NiCuZn ferrite nanoparticles from metallic nitrate solutions using the microwave direct denitration method and evaluation of its properties
Published in Particulate Science and Technology, 2021
Achmad Dwitama Karisma, Yoshihiro Shinokawa, Tomonori Fukasawa, Toru Ishigami, Kunihiro Fukui
The magnetization characteristic of the spinel material depends on the composition, the additive material, and its microstructure (He et al. 2015). The magnetization of soft ferrite is induced by domain rotation and wall motion, which are affected by particle size and the sintered particle density (Fukui et al. 2012). Moreover, the porosity of the material, which is inversely proportional to the density parameter, also plays a role in controlling the magnetization properties of the material. However, porosity hinders the domain wall motion (Mohit, Gupta, and Rout 2014). To address these factors, the effect of the sintering treatment on the densification and the magnetic properties of the product was investigated. Table 1 shows the relative densities of the sintered pellets produced from ferrite powders obtained by both methods under various reaction temperatures. The relative density was defined as the ratio of the bulk density to the true density. The bulk density of the pellet was determined using the Archimedes method and the true density of the NiCuZn ferrite is 5.38 g/m3 (Barba et al. 2004). The relative density of the sintered pellet obtained by the MDD method was higher than that from the SSR method, irrespective of the reaction temperature. This may be because the primary particle size obtained by the MDD method is much smaller than that by the SSR method as shown in Figure 6. Here, the reason why the density of the pellet by the MDD method decreases more than 900 °C may be caused by the gasification or evaporation of the intermediate or impurities which is not complete the oxidization reaction. In summary, the MDD method can provide a higher density for the pellet of the NiCuZn ferrite product powder.
A review of production, properties and advantages of biodiesel
Published in Biofuels, 2018
Vijay Kumar Mishra, Rachna Goswami
Weight per unit volume defines the density of a fuel. Oils are denser having more energy [3]. The density of biodiesel can measured according to EN ISO 3675/12 185 and ASTM D1298 standard. With this reference standard, density should be tested at the temperature reference of 15 or 20°C [99]. Relative density is the density of the fuel compared to the density of water. The relative density of biodiesel is required to make mass to volume conversions, calculate flow and viscosity properties, and is used to determine the homogeneity of biodiesel tanks [3].