Measurement of Water Content

Control tests on the moulding powder include measurement of water content, flow, powder density and rate of cure. 

A slow non-competing liquid/liquid reaction with no catalyst present gave only 78 % O-alkylation. Thus the active site of the lipophilic phosphonium ion catalysts appears to be aprotic, just as in analogous phase transfer catalyzed alkylations with soluble quaternary ammonium salts 60), Regen 78) argued that the onium ion sites of both the 17% and the 52% RS tri-n-butylphosphonium ion catalysts 1 are hydrated, on the basis of measurements of water contents of the resins in chloride form. Mon-tanari has reported measurements that showed only 3.0-3.8 mols of water per chloride ion in similar 25 % RS catalysts 74). He argued that such small hydration levels do not constitute an aqueous environment for the displacement reactions. No measurements of the water content of catalysts containing phenoxide or 2-naphthoxide ions have been reported. 

Skin surface conductance OS) was determined with Skicon-100 (IBS Company, Hamamatsu, Japan) by measurement of water content in SC. Nine measurements were repeated at a single point, and the mean was taken after excluding the highest and lowest values. 

The droplet can be as small as 2.5 nL and exhibit amazingly good accuracy and precision, allowing delivery of compounds in assay-ready condition in any format available. Since nothing is in contact with the source compound, cross contamination is not a concern. The non-contact nature of the instrument also saves time and money—no need for tip washing or buying disposable tips. An added benefit is the fairly accurate measure of water content in the well (Ellson et al., 2005). 

A better view of the extent of the void volume available within a zeolite comes from simple measurements of water content as hsted in Table 28. Zeolites with high voidage (e g. ETA, CHA, FAU) can be assumed to have only 1% of their usefiil surface on the exterior of the crystal. 

Potts, R. O. In vivo measurement of water content of the stratum comeum using infrared spectroscopy A review. Cosmetics and Toiletries 700 27-31, 1985. 

The combination of membranes and sensors has been mentioned in the literature as a potentially interesting field. To date, however, very few examples of applications have been realised. The measurement of water content in soils and in underground rock formations is potentially interesting as has been proved by field tests [11],... 

Measurements of water content after exposure until equilibrium is reached at various constant humidities yield objectively the practical... 

Analytical methods used to determine the final stability of the broken or unbroken emulsion have varied. It has been shown that measurements of water content yielded unreliable results [J5S, J63], Viscosity measurements show correlation to emulsion stability and provide a more reliable measure of emulsion stability but special instrumentation is required [J69, 170], Simple viscometers without controlled shear or stress rates yield unreliable results. 

T. Suzuki, Y. Tabuchi, S. Tsushima, S. Elirai, Measurement of water content distribution in catalyst coated membranes under water permeation conditions by magnetic resonance imaging, Int. J. Hydrogen Energy 36 (2011) 5479—5486. 

Pena y Lillo, M., Perez-Correa, R., Agosin, E. and Latrille, E., 2001, Indirect measurement of water content in an aseptic solid substrate cultivation pilot-scale bioreactor. Biotech. Bioengn., 76(1) 44-51. 

Measurements of water content showed that undried cellulose pulp contained approximately 7% bound water. Cellulose containing 7% of both added and bound water can form high concentration and anisotropic cellulose solutions. The flow rate behavior of cellulose solutions, containing 7% water (both added and bound water), were similar to that of solutions prepared with predried cellulose. This means that the presence of water up to 7% did not affect... 

In addition to the characterization of cell structure modification, nondestructive measurements of water content, of local tissue structures and porosity, and of temperatures before and during drying, are required in order to... 

The contents of Li and B in concrete samples and the contents of Li, B, K, and Ca in rebar samples were analyzed by atomic absorption spectrophotometry. Nitrogen contents in concrete were analyzed by Kjeldahl-method. The concentrations of hydrogen were derived from measurements of water content in concrete using thermogravimetric analysis. 

McKenna-Neuman, C. and Langston, G. 2006. Measurement of water content as a control of particle entrainment by wind. Earth Surface Processes and Landforms 31(3) 303-317. 

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