Manometric

In view of the sensitivity of the manometric system, which has a full scale range of about 2 mm of mercury, the final pressure must be reached in stages, repeating the operations described a number of times. 

After World War II, analytical methods for amino acids were improved and new methods were iatroduced. The first was microbial assay usiag lactic acid bacteria which require all of the regular amino acids for growth. Manometric determiaation (by use of a Warburg manometer) of CO2 Hberated by the... 

Manometric determiaation of L-lysiae, L-argioine, L-leuciae, L-ornithine, L-tyrosiae, L-histidine, L-glutamic acid, and L-aspartic acid has been reviewed (136). This method depends on the measurement of the carbon dioxide released by the T.-amino acid decarboxylase which is specific to each amino acid. 

The inverted differential U tube, in which the manometric fluid may be a gas or a hght liquid, can be used to measure hquid pressure differentials, especially for the flow of slurries where solids tend to settle out. Additional details on the use of this manometer can be obtained from Doolittle (op. cit., p. 18). 

Closed U tubes (Fig. 10-10) using mercuiy as the manometric fluid serve to measure direclly the absolute pressure p of a fluid, provided that the space between the closed end and the mercury is substantially a perfect vacuum. 

Change of manometric fluid. In open manometers, choose a fluid of lower density In differential manometers, choose a fluid such that the difference between its density and that of the fluid being measured is as small as possible. 

For liquid film seals, an overhead tank is normally used. The tank functions as part of the differential pressure control. The process gas is referenced to the top of the tank, and the tank s physical height becomes a manometric leg. The oil level is controlled in the tank. Figure 8-11 shows an alternate arrangement for the overhead seal tank, including the recommended operating levels and volumes. The material of the seal oil tank should be stainless, the same as that recommended for the accumulator. 

The compound MgGa204, when activated by divalent impurities such as Mn +, is used in ultraviolet-activated powders as a brilliant green phosphor. Another very important application is to improve the sensitivity of various bands used in the spectroscopic analysis of uranium. Minor uses are as high-temperature liquid seals, manometric fluids and heat-transfer media, and for low-temperature solders. 

This Crude product (15.8 g) In water (360 ml) was added to a prehydrogenated suspension of 10% palladium on charcoal (4 g) in water (400 ml), and hydrogenation was continued for 30 minutes. The catalyst was removed and the filtrate was adjusted to pH 7.5 with sodium bicarbonate, then evaporated at low temperature and pressure. The residue was purified by chromatography on a column of cellulose powder, eluting first with butanol/ ethanol/water mixture and then with acetone/isopropanol/water. The main fraction was evaporated at low temperature and pressure to give a 32% yield of the sodium salt of a-carboxybenzylpenicillin as a white powder. The product was estimated by manometric assay with penicillinase to be 58% pure. 

Manometric and volumetric methods (kinetics) Thermogravimetry (kinetics from very thin films to thick scales stoichiometry) Electrical conductivity of oxides and allied methods (defect structures conduction mechanisms transport numbers) Radioactive tracers and allied methods (kinetics self diffusion markers)... 

To measure gas and water vapor permeability, a film sample is mounted between two chambers of a permeability cell. One chamber holds the gas or vapor to be used as the permeant. The permeant then diffuses through the film into a second chamber, where a detection method such as infrared spectroscopy, a manometric, gravimetric, or coulometric method isotopic counting or gas-liquid chromatography provides a quantitative measurement (2). Die measurement depends on the specific permeant and the sensitivity required. 

Manometric Stability Tests. Based on press measurements developed by gases formed on decompn of ex pis. Am on this group of tests are (1) Brame s Method, (2) Chiaraviglio and Corbino Method, (3) Desmaroux Method, (4) Dupre s-Vacuum Test, (5) Farmer s Vacuum Stability Test, (6) Haid, Becker Dittmar Test, (7) Meerscheidt-Hullassem s Test, (8) Mittasch s Method, (9) Obermuller s Method, and (10) Talliani Test... 

Its rate of detonation, as detd by the Dautriche method, was about the same as that of TNT (6880m/sec). Its sensitivity to impact, as detd in Fr, was considerably lower than for PA, but according to tests conducted in Engl, TNPht was more sensitive than PA (Ref 8). When pellets of TNPht (d 0.25g/cc) were fired in a manometric bomb, the pressure developed was 2490kg/sq cm, as against 3230 for PA... 

Thermal Decomposition. The definitive study of the thermal decompn of PA was made by Andreev and Uu Pao-Feng (Ref 34). They followed the decompn of liq PA manometrically over the temp... 

Carbon was estimated by a variation of the Van Slyke method.(2) A 30-100 mg sample was heated for 30 minutes with 0.5 g K2Cr207, lg KIOj, 10 mL 20% fuming H2S01( and 5 mL HjPO in a closed flask swept by a purified N2 stream. The N2 stream carried the evolved C02 to an absorption solution of 0.5M Na0H-0.3M N H. After the wet combustion, the absorbed C02 was released from an aliquot of the NaOH solution with lactic acid in a manometric apparatus. Corrections were applied for the vapor pressure of water and for reagent blank. 

Hanstveit R (2003a) Trichloromethylstannane (CAS 993-16-8) Determination of the ready biodegradability in a manometric respiration test Delft, TNO, September (Repert Ne. V2492/01). 

Hanstveit R (2003f) Determination of the ready biodegradability of dichlorodioctylstannane in a manometric respiration test. 

The reversible oxygenation of Fe(DMG)2 (B)2 in aqueous dioxane solution, as monitored by reversible changes in the visible absorption spectrum and manometric oxygen evolution, has been reported (55), but in a more recent study 54) it was not possible to confirm the earlier findings. However it was established that there was a slow irreversible... 

The lower esophageal sphincter is a manometrically-defined zone of the distal esophagus with an elevated basal resting pressure. The sphincter is normally in a tonic, contracted state, preventing the reflux of gastric material from the stomach. It relaxes on swallowing to permit the free passage of food into the stomach. 

Various aspects of in vitro gas production test have been reviewed by Getachew et al. [33], and these authors reported that gas measurement were centered on investigations of rumen microbial activities using manometric measurements and concluded that these methods do not have wide acceptability in routine feed evaluation since there was no provision for the mechanical stirring of the sample during incubation. Another in vitro automated pressure transducer method for gas production measurement was developed by Wilkins [34], and the method was validated by Blummel and Orskov [35] and Makkar et al. [36]. There are several other gas-measuring techniques such as (i) Flohenheim gas method or Menke s method [37] (ii) liquid displacement system [38] (iii) manometric method [39] (iv) pressure transducer systems manual [40], computerized [41], and combination of pressure transducer and gas release system [42]. 

Pressure measurements can be accomplished by any one of a number of different types of manometric devices without disturbing the system being observed. Another type of reaction system that can be monitored by pressure measurements is one in which one of the products can be quantitatively removed by a solid or liquid reagent that does not otherwise affect the reaction. For example, acids formed by reactions in the gas phase can be removed by absorption in hydroxide solutions. 

Perhaps conceptually one of the simplest tests for comparing the stability of related polymer samples is that of measuring oxygen uptake. In such a measurement the amount of oxygen reacting with a polymer sample, at a particular temperature and over a specific time, can be measured either manometrically or volumetrically, by a relatively simple device [1], such as that illustrated in Figure 4 [10]. Whereas such a measurement may be made on solid samples, such as sheet, powder or film, in order to minimise errors, the measurement is preferably made on thin film samples. 

Narducci, F., Bassoti, G., Baburri, M., Morelli, A., Twenty four hour manometric recording of colonic motor activity in healthy man, Gut... 

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