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Sampling of liquids

In the sections that follow, these three steps are considered for the sampling of liquids (including solutions), gases, and solids. [Pg.193]

Lovelace, B. G. 1979. Safe Sampling of Liquid Process Streams. Chemical Engineering Progress [Nov]. Also published in Vol. 13, C.E.P. Technical Manual. [Pg.152]

Acetone is widely used as a nail polish remover. A sample of liquid acetone is placed in a 3.00-L flask and vaporized by heating to 95°C at 1.02 atm. The vapor filling the flask at this temperature and pressure weighs 5.87 g. [Pg.110]

In a chemical system, mass will flow until equilibrium is achieved. Consider, as an example, the approach to equilibrium between the liquid and gas phases of a substance. If a sample of liquid is introduced into an evacuated closed container, the liquid will begin to evaporate to form a gas phase. If one measures the pressure of this gas as a function of time, a graph similar to that shown in Figure 5.5 will be obtained.0 The pressure at first increases rapidly. After a short time period, however, it levels off at the value represented by p. ... [Pg.225]

When heat is supplied at a constant rate to a sample of liquid water, the temperature rises to 100 °C and then remains constant until all the water has evaporated. [Pg.803]

The melting point of carbon dioxide increases with increasing pressure, since the solid-liquid equilibrium line on its phase diagram slopes up and to the right. If the pressure on a sample of liquid carbon dioxide is increased at constant temperature, causing the molecules to get closer together, the liquid will solidify. This indicates that solid carbon dioxide has a higher density than the liquid phase. This is true for most substances. The notable exception is water. [Pg.207]

Tapia, O., Colonna, F. and Angyan, J. G. Generalized self-consistent reaction field theory in multicenter-multipole ab initio LCGO framework. I. Electronic properties of the water molecule in a Monte Carlo sample of liquid water molecules studied with standard basis sets, J.ChimPhys., (1990), 875-903... [Pg.353]

Breakdown to N02, 02 and H20 of gaseous anhydrous nitric acid under y-irradiation has been studied at 25 °C by Dmitriev et a/.308 who also irradiated samples of liquid and solid nitric acid over the temperature interval from —196 to + 32 °C. The esr spectrum of solid HN03 showed the presence of N03 and N02 radicals. The radiational breakdown of HN03 appears to be principally through rupture of the weakest H0-N02 bond. [Pg.104]

Sampling of liquids may be carried out by following these procedures ... [Pg.7]

Several factors determine how fast a sample of liquid will evaporate. [Pg.50]

The scission reaction was carried out with a fixed addition of 1.50g of the dry resin, 10 mg of ferrous sulfate heptahydrate and 50 ml of 3% w/v hydrogen peroxide in a round Pyrex flask. The evolved carbon dioxide was vented to the atmosphere through serial traps containing sulfuric acid followed by a soda lime sorption tube. The magnetically stirred reaction flask was submerged in an oil bath heated with an immersed electrical coil and a magnetic stirrer positioned below the bath. The temperature was maintained at 50 +/- 1 C. After varied times 1.0 ml samples of liquid were withdrawn. There were fewer than six withdrawals in a given reaction sequence. [Pg.357]

In a variation of the photoelectric method, Fq can be determined by measuring the emission of electrons from the liquid into the vacuum. Even when Fq is negative, electrons can penetrate this barrier and be collected in the gas phase [35,36,47]. Borghesani et al. [48] used this technique and from the time evolution of the current reaching the anode for a sample of liquid Ar at 87 K found Fq to be —0.126 eV. This is in excellent agreement with the value of —0.125 eV given by Eq. (6) (see below) for this density (2.09 x 10 cm ) using the field ionization technique. [Pg.180]

Figure 5. Energy as a Junction of temperature of a 80 molecule sample of liquid water. The runs underlying each datapoint are longer in (a) than in (b). Figure 5. Energy as a Junction of temperature of a 80 molecule sample of liquid water. The runs underlying each datapoint are longer in (a) than in (b).
Prior to the removal of the film from the gel block, samples of liquid were rapidly removed at various temperature levels and their viscosities measured on a Ferranti-Shirley cone plate viscometer at 20°C. The amount of material required fcr each measurement was very small and enough could be obtained by making one pass with a small spoon spatula across the width of the plastisol. At a temperature... [Pg.158]

Three conformations for a molecule of -pentane. The molecule looks different in each conformation, but the five-carbon framework is the same in all three conformations. In a sample of liquid w-pentane, the molecules are found in all conformations— not unlike a bucket of worms. [Pg.394]

A sample of liquid of density 0 85 g/ml weighs 32 3524 g in air with brass weights What is the weight in vacuo 7... [Pg.100]

The sampling of liquid mixtures in GC is usually done by means of microliter syringes through a self-sealing silicone septum. The... [Pg.305]

Experiments were carried out in a 0.3 litre stirred autoclave (Autoclave Engineers type Magne-Drive) operating in a batch mode andequipped with a system for sampling of liquid during the course of the reaction... [Pg.121]

The reactions were carried out in a 0.1 liter stirred autoclave operating in a batch mode and equipped with a system for sampling of liquid during the reaction. The autoclave was charged with the substrate together with solvent and the freshly calcinated zeolite (calcination overnight at 500°C or 400°C in air, prior to use) and then heated to the desired temperature. The amounts of zeolite and of distilled water depend both on the nature and the concentration of substrate. Samples were withdrawn periodically and analyzed by g.l.c..Two typical examples are described below ... [Pg.566]

Sampling of materials consisting of more than one phase at the sampling point is particularly difficult. Common examples are the sampling of liquid or vapour from a plate absorber or distillation column or from a packed column, or the sampling of a multiphase mixture flowing in a pipe or duct. In such cases it is not always known whether the liquid or vapour has been sampled or some combination of both. [Pg.528]

Even when composition is fixed, viscosity and other rheological properties may depend on the size and arrangement of aligned domains within a sample of liquid crystalline material. No studies of this matter seem to have been made, however. Such structural characteristics do influence electrical conduction and diffusion in liquid crystals, as discussed further below. [Pg.97]

In 1979, because of a lack of large samples, boiler fuel test programs will be limited to small scale equipment. However, in 1980, large samples of liquids in the 5,000-10,000 barrel range should become availabel from the H-Coal pilot plant at Catlettsburg, Kentucky and the Exxon Donor Solvent process at Baytown, Texas. It would be preferable to run a number of tests utilizing different utility sites and types of electric generation... [Pg.24]

Why is it necessary to mix samples of liquid A and liquid B together before polymerization proceeds Could we add a little catalyst to liquid A, say, and achieve the same effect (as we did in the free radical polymerization experiment) ... [Pg.237]

Samples were taken from the precipitated bottom phase, the solvent phase, and the C02 vapour phase. The sampling procedure for the bottom phase depended on whether the precipitate was a liquid (triglyceride oil), solid (lecithin) or a mixture of both components. Samples of liquid bottom phase were withdrawn from valves V3 and V16 positioned at the base of the view cell, with valve VI shut. Valves V5, V6 and V2 were opened to ensure constant pressure inside the view cell during sampling. Samples of solid lecithin were recovered by first removing the solvent phase under pressure as above, followed by depressurization, and then solvent washing of the apparatus. Lecithin was retained on a filter placed above valve V3. For mixtures of lecithin and Soya oil, the two sampling procedures were combined. The Soya oil was first removed under pressure, followed by the solvent phase. The apparatus was then depressurized and solvent washed. Samples of the solvent phase at pressure were also taken via valve V4 and collection vessel CV3, to measure the C02 content, and the concentration of solute still in solution. [Pg.310]


See other pages where Sampling of liquids is mentioned: [Pg.752]    [Pg.822]    [Pg.1041]    [Pg.314]    [Pg.35]    [Pg.296]    [Pg.11]    [Pg.78]    [Pg.129]    [Pg.140]    [Pg.372]    [Pg.216]    [Pg.396]    [Pg.168]    [Pg.21]    [Pg.78]    [Pg.123]    [Pg.11]    [Pg.204]    [Pg.113]    [Pg.226]    [Pg.169]    [Pg.104]    [Pg.13]    [Pg.116]    [Pg.97]    [Pg.4]   
See also in sourсe #XX -- [ Pg.53 ]




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Liquid samples

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