Monitoring of moisture

J. Rantanen, S. Lehtola, P. Ramet, J. Mannermaa, J. Yliruusi, On-line monitoring of moisture content in an instrumented flnidized bed grannlator with a multi-channel NIR moistnre sensor. Powder TechnoL, 99(2), 163-170... 

R.L. Green, G. Thurau, N.C. Pixley, A. Mateos, R.A. Reed and J.P. Higgins, In-line monitoring of moisture content in fluid bed dryers using near-IR spectroscopy with consideration of sampling effects on method accuracy. Anal. Chem., 77(40), 4515 522 (2005). 

Rantanen J, Lehtola S, Ramet P, Mannermaa JP, Ylirussi J. On-line monitoring of moisture content in a instrumented fluidized bed granulator with multichannel NIR moisture sensor. Powder Technol 1998 99 163-170. 

TABLE 6.14. Techniques Suitable for the On-line Monitoring of Moistur... 

Prohling or imaging of a physical variable, e.g., monitoring of moisture diffusion process through an organic material is readily accomplished with low frequency dielectric sensors. Alternatively, a microwave probe can be used, but the sample penetration depth of the microwave probe would be limited, in many cases, to a few microns, whereas the penetration depth of low frequency dielectric measurements can be controlled by changing the separation between the sensor head electrodes. 

Fiber optic sensors can be made sensitive for monitoring of moisture ingress or chemical species. There are both local sensors and distributed sensors [51-... 

Yeo, T.L., et al. Fibre-Optic Sensor for the Monitoring of Moisture Ingress and Porosity of Concrete. 17th Int. Conf on Optical Fibre Sensors (OFS-17), Bruges, Belgium, SPIE-Vol. 5855 (2005), pp. 491-494... 

McColl D, Cartlidge B, Connolly P (2007) Real-time monitoring of moisture levels in wound dressings in vitro an experimental study. Int J Surg 5(5) 316-322, http //dx.doi.0rg/lO.lOl6/J. ijsu.2007.02.008... 

Specifications and Standards. Typical specifications for phthahc anhydride are given in Table 10. AH specifications are measures of purity. Sohdification point is a sensitive indicator of absolute purity, and is a key specification. Another key specification is molten color stabiUty, which is the color after being held at 250°C for two hours. This test ensures acceptable color after shipment in molten form and detects the presence of impurities that can cause discoloration at elevated temperatures. Phthahc acid level is a monitor of how well moisture has been excluded during storage and shipment. 

Cost Costs were estimated at 4.5 million, which includes soil importation, revegetation, quality control and assurance, construction management, and installation and operation of moisture monitoring systems. 

PESTAN (12) is a dynamic TDE soil solute (only) model, requiring the steady-state moisture behavior components as user input. The model is based on the analytic solution of equation (3), and is very easy to use, but has also a limited applicability, unless model coefficients (e.g., adsorption rate) can be well estimated from monitoring studies. Moisture module requirements can be obtained by any model of the literature. 

Denitrification, a dissimilatory pathway of nitrate reduction (see Section 3.3 also) into nitrogen oxides, N2O, and dinitrogen, N2, is performed by a wide variety of microorganisms in the forest ecosystems. Measurable rates of N20 production have been observed in many forest soils. The values from 2.1 to 4.0 kg/ha/yr are typical for forest soils in various places of Boreal and Sub-Boreal Forest ecosystems. All in situ studies (field monitoring) of denitrification in forest soils have shown large spatial and temporal variability in response to varying soils characteristics such as acidity, temperature, moisture, oxygen, ambient nitrate and available carbon. 

C. Buschmilller, W. Wiedey, C. Doscher, J. Dressier and J. Breitkreutz, In-line monitoring of granule moisture in fluidized-bed dryers using microwave resonance technology, Eur. J. Pharm. Biopharm., 69, 380-387 (2008). 

A. Gupta, G.E. Peck, R.W. Miller and K.R. Morris, Real-time near-infrared monitoring of content uniformity, moisture content, compact density, tensile strength, and Young s modulus of roller compacted powder blends, J. Pharm. Sci., 94(7), 1589-1597 (2005). 

Buschmuller et have demonstrated that microwave resonance can be used effectively as means to monitor the moisture levels in a fluidized-bed dryer during the granulation process. The penetration depth of microwave resonance may be limited to a few microns, and hence this technique may not have any real advantages over NIR which has also been used for monitoring moisture in dryers, and has the advantage of providing chemical information such as solvent levels in addition to water, and other important properties such as polymorphic form, and particle size. 

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