Moisture content determination

Moisture-content determinations provide data for estimating soil compaction and compressibility. If a soil is saturated, no volume change can occur without intake or discharge of water. 

Moisture content determined by redrying procedure at 70° C., indicated by horizontal line crossing ordinate at 7.4%. 70° C. curve intersects horizontal line at approximately 35 hours (not shown in graph see Table IV in 18)... 

The amount of water present is fundamental to the stability of confectionery products. Unsurprisingly, therefore, measuring water content is an important exercise. Various methods are used. Some oven drying moisture content determinations are still carried out. This sort of work is difficult since the moisture contents are normally low and the samples can only be dried with difficulty. In particular, there are problems in drying the product in a reasonable time without charring it. Various other methods of water content determination are in use. One such is the Karl Fischer titration. 

The adsorption of contaminants on geosorbents also is affected by climatic conditions reflected in the subsurface temperature and moisture status. Calvet (1984) showed how the soil moisture content may affect adsorption of contaminants originating from agricultural practices. The moisture content determines the accessibility of the adsorption sites, and water affects the surface properties of the adsorbent. The competition for adsorption sites between water and, say, insecticides may explain this behavior. Preferential adsorption of the more polar water molecules by soil hinders... 

Moisture Content Determination by Karl Fisher (KF) Method. 

Specific Gravity and Moisture Content Determine the sp gr by means of a 50ml pycnometer at exactly 15.6/15.6° or determine it at other temps and calculate for 15.6/1 5.6°as follows ... 

Samples can be dried and moisture content determined by special methods [19] and soil samples can be homogenised with a blender or a similar device. 

Water (moisture) content determination Quick sample heating Microscopic sample preparation Sample incineration and melting... 

After the extraction is completed, typically the specimen is removed and measured to calculate its volume, weighed and oven dried at 105 °C for density and moisture content determinations. 

IMEP graphs are given. These graphs present the information retrieved from the questionnaire. Results in IMEP on solid samples have to be reported as content values corrected for dry mass. There is no protocol prescribed for moisture content determination. Participants are free to use their routine method. The majority of IMEP participants apply the oven-drying method at a certain temperature with or without prior equilibration of the sample at ambient conditions. Other questions regard the time needed for the analysis, the experience of the participants, and their regular participation in PT schemes. 

Prior to weighing, the test samples are conditioned for at least 20min in the atmosphere near the balance A pulp sample which will consume approximately 50% of the potassium permanganate solution is weighed out to the nearest 0 001 g (Note 1) The consumption must be between 30 and 70% At the same time a second sample is weighed and its moisture content determined... 

Experiment 2 Soil Moisture Content Determination, Examination of Soil Microorganisms via Microscopic and Cultural Assays... 

The nature of moisture content determinations is perhaps best exemplified by the fact that the Handbook of Pharmaceutical Excipients lists 31 separate versions of laboratory tests to determine moisture content and one to determine equilibrium moisture content. These methods were used to assess the moisture content in the compilation of 148 monographs, many of which do not deal with solids. 

Thermal gravimetric analysis (TGA) is undoubtedly the most widely used method of moisture content determination. The sensitivity and sophistication of TGA instruments ranges from the classical moisture balance (LOD) to specially designed microbalances enclosed in chambers that may be evacuated. Microprocessor control of the temperature increase has led to more reproducible and discriminating information. 

Moisture determination in connexion with large-scale yarn purchasing is usually carried out in specially-designed conditioning ovens. These are not commonly required by dyers and finishers. It is, however, often desirable to carry out quick moisture-content determinations for routine process control. The small, rapid regain apparatus shown in Fig. 2.14 is suitable for this. It consists of an air heater and a blower which impels a stream of hot air over the sample to be tested. 

Figure 1 Variation of moisture content determined using drying method IDF standard 26A in cows whole milk collected from four dairy farms.

Moisture is not a grade-determining factor, but moisture is determined on all soybean samples. Moisture content determines how much dry matter is bought or sold. It is also very important for assessing storability, and it affects end-use value. The official... 

The material was dried at 55 °C in air for 100 h. The moisture content determined at this stage was less than 3%. The material was then sieved... 

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