Concentration by volume

Example 2 LNG Dispersion Tests Britter and McQnaid (1988, p. 70) report on the Burro LNG dispersion tests. Compute the distance downwind from the following LNG release to obtain a concentration equal to the lower flammability limit (LFL) of 5 percent vapor concentration by volume. Assume ambient conditions of 298 K and 1 atm. The following data are available ... 

For example, the lower flammability limit of methane in air at sea level is a concentration (by volume or partial pressure) of about 5%. The upper flammability limit is about 15% by volume or partial pressure. Heavier hydrocarbons tend to have lower LFLs. The LFL and UFL of some common hydrocarbons are given in Table B-2. 

Ethylene Glycol Concentration by Volume Boiling Point ... 

Because the volume occupied by each molecule is similar at low pressures, the concentration by volume is equal to the concentration by moles, and nmeth/Wair = 2 x 10 . Therefore, Pmeth/Fair = 2 x 10 . This means that the two are interchangeable. At one atmosphere total pressure, then, the methane partial pressure for this example... 

Vinylidene fluoride is taken up rapidly via the pulmonary route in rats, but at equilibrium the mean concentration (by volume) in rats was only 23% of that in the gaseous phase. Metabolism proceeded very slowly and was saturable at exposure concentrations of about 260 mg/m Its maximum rate was 1% that of vinyl chloride and less than 20% that of vinyl fluoride there has been a report of an increase in the urinary excretion of fluoride in exposed rats. No alkylating intermediate was demonstrated after passage through a mouse-liver microsomal system. However, vinylidene fluoride inhibits mixed-function oxidase activity in vitro and, like similar halogenated compounds that are transformed to reactive metabolites, it alters rat intermediary metabolism, leading to acetone exhalation (lARC, 1986). 

The density of energy in the pipeline is far lower for biomass than for oil. The present work is based on 30% biomass by volume in a carrier liquid. Wasp et al. (6) based their work on 22% biomass. Brebner (4) and Elliott (5) indicated that at about 47% concentration by volume a slurry of wood chips and water cannot flow. Given the low heat content of wood per unit volume relative to oil and the low concentration of wood chips in water, the energy density in a 30% wood chip slurry is about 8% compared to oil, even based on HHV, and hence far larger pipelines are required to transport the same amount of energy. 

What is the affinity (driving force) of the reaction CO + 02v 2C02 in the atmosphere, where concentrations (by volume) are approximately 21% 02, 300ppm (parts per million) C02, and lOOpb (parts per billion) CO ... 

Figure 12 is a plot of the surface of constant 4.1% hydrogen concentration by volume. 

Figure 14 is a plot of the surface of constant 2.1% propane concentration by volume. The cloud covering the entire floor of the garage represents the volume of burnable gas after 2 hours of leakage at 4,334 litersh. The cloud had reached essentially this size at 20 minutes. 

Combustions of gas-air mixtures as self-sustained chemical reactions occur only within well-defined volumetric ratios. The gas concentration - by volume - is limited by a lower value - Lower Explosive Limit (LEL) - and an upper value - Upper Explosive Limit (UEL) - in order to maintain an expanding reaction zone in the gas-air mixture. Below the LEL and above the UEL an explosive gas-air atmosphere will not be formed. Table 1.1 summarizes LEL and UEL for gases in chemical plants, the oil and gas industry and in coal mines. 

The originators of the Penn Kem system claim that it is capable of measuring particle size distributions in the size range 0.01 to 100 pm for slurry concentrations at volume concentrations as high as 50%. They report experimental work with an on-line system using titanium dioxide at volume concentrations from 3.5% to 42.3%. Quantitative comparison of data was carried out at eighteen frequencies and eleven concentrations by volume [248,249]. Theoretical work resulted in the development of a unified coupled phase model which successfully predicted the experimental data for suspensions, emulsions and aerosols [250]. 

ATEE, acetyl-L-tyrosine ethyl ester ATryEE, acetyl-L-tryptophan ethyl ester. The numbers below each ester represent methanol concentrations by volumes. 

These figures might lead us to assume that the osmotic pressures, and the colligative properties which are proportional to them in moderately concentrated solutions, were proportional to the concentration by weight and not to the concentration by volume. This again would appear to be a serious objection to Digitized by Microsoft ... 

A water analysis will usually report the levels of ionic constituents in terms of their actual mass concentration by volume in milligrams per litre (mgU ) or parts per million (ppm). Very low concentrations of trace constituents are often reported as micrograms per litre (/agU ) or parts per billion (ppb). Numerically the values for (mgU and ppm) or (/agU and ppb) are taken as being equal for very dilute aqueous solutions of density close to that of pure water at 4 °C, although by definition the units are not identical. 

Filter at approx 20 psi nitrogen with constant stirring, at 4°C (approx 3-5 h), ensuring that the membrane is not allowed to dry. This will result in approx a 40-fold concentration by volume. HBV DNA content in the concentrated sample is quantitated by blot hybridization against a known standard quantity of HBV DNA standard (see Note 1). 

The most convenient way of determining ethanol concentration is by measuring the density and temperature of the solution and relating this to concentration by the use of appropriate tables. The concentration by volume determined in this way can then be related to the British proof system, or to the Sikes scale for specification on the bottle. 

The density system is used in a number of countries to determine alcohol concentration. The United States uses a simpler proof system based on 100% alcohol being equivalent to 200° proof. Fractions of this concentration, by volume, are specified by multiplying the concentration, in percent by volume, by two (Table 16.10). In France, alcohol concentrations in spirits are simply specified as percent alcohol by volume, sometimes referred to as the Gay-Fussac system. Percent alcohol by weight is used in Germany. 

The acute toxicity of ethrane by inhalation, ingestion, or intraperitoneal or subcutaneous applications in rodents was found to be low to very low at concentrations of <1000 ppm in air or dosages below 1000 mg/kg. In humans it causes anesthesia at 1.5-2% concentrations (by volume of air). Exposure to concentrations above this level can be dangerous. The target organs are the central nervous system, cardiovascular system, kidney, and bladder. The symptoms are anesthesia, respiratory depression, and seizure. Hypotension can occur due to its action on the cardiovascular system. Exposure to a 1% concentration in air for 6 hours caused anuria in humans. 

CgHiiOg 2C2H5OH + 2CO2 Yeast is used to cause the reaction. At about 15% alcohol concentration (by volume) the reaction stops because the yeast is killed. Higher concentrations of alcohol are produced by distillation. 

A doped device structure was fabricated with a configuration of ITO/ PEDOT PSS/NPB (40nm)/NPB perylene (40nm)/NPB (40nm)/Ca/Al, where perylene was doped at 10% concentration by volume. The JVL characteristics of the perylene-doped NPB device are shown as the open symbols in Figure 3.26. Detailed performances of the undoped and perylene-doped NPB devices are summarized in Table 3.6. Compared to the undoped device, the current efficiency of perylene-doped device was enhanced seven times to about 0.7 cd/A at SOmA/cm, and the maximum luminance also increased to... 

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