Moisture analysis tests

Another important and frequently used test throughout the industry is the moisture analysis test. This simple but effective test provides useful information regarding the processibility of plastic materials. Excessive moisture can cause many processing and visual problems such as splay marks. Bulk density tests and sieve analysis tests also help to predict the material s behavior during mixing, compounding, and processing. Chapter 7 discusses analytical tests often used in material characterization. 

The hygroscopic nature of plastic materials causes processing as well as dimensional stability problems. Materials like ABS and polycarbonate must be dried thoroughly before processing to avoid splay marks on molded parts, loss of impact strength, and loss of other properties. The presence of moisture also tends to produce a weak weld or knit lines, further weakening the molded part. Many processors conduct routine moisture analysis tests on materials prior to processing. Five basic methods have been developed and are most frequently used. 

Proximate Analysis. This includes (he determination of total moisture, volatile matter, and ash and the calculation of fixed carbon for coals and cokes. The term Proximate" should not be confused with Ihe word approximate." since all Proximate Analysis tests are performed according lo rigid specifications and tolerances. Proximate Analysis results may be used lo establish the rank of coals to show the ratio of combuslible lo incombustible constituents, lo provide the basis for buying and selling coal, and to evaluate for beneliciation, or other purposes. 

Total moisture of coal Ultimate analysis of coal Ultimate analysis of coke Chlorine in coal and coke Phosphorus in coal and coke Arsenic in coal and coke Analysis of coal ash and coke ash Determination of moisture-holding capacity of hard coal General introduction and methods for reporting results Determination of total moisture of coke Proximate analysis, determination of moisture content of the general analysis test sample... 

ISO 11722. Hard Coal Determination of Moisture in the General Analysis Test Sample by Drying in Nitrogen. 

When aqueous and solid samples were analyzed for moisture and content of sugars, lignin and other chemicals, the procedures described in the NREL Chemical Analysis Testing Standard Procedure LAP no. 001-014 (16) were followed. The analysis of aqueous samples was carried out by two HPLC units a Bio-Rad (Hercules, CA) Aminex HPX-87P column for analysis of sugars, and a Bio-Rad Aminex HPX-87H column for analysis of acid and other compounds, respectively. Samples were run at 65°C and eluted at 0.6 mL/min with 5 mM H2S04 for the HPX-87H column, and 85°C and 0.55 mL/min with pure water for the HPX-87P column. 

In essence, the test battery should include XRPD to characterize crystallinity of excipients, moisture analysis to confirm crystallinity and hydration state of excipients, bulk density to ensure reproducibility in the blending process, and particle size distribution to ensure consistent mixing and compaction of powder blends. Often three-point PSD limits are needed for excipients. Also, morphic forms of excipients should be clearly specified and controlled as changes may impact powder flow and compactibility of blends. XRPD, DSC, SEM, and FTIR spectroscopy techniques may often be applied to characterize and control polymorphic and hydrate composition critical to the function of the excipients. Additionally, moisture sorption studies, Raman mapping, surface area analysis, particle size analysis, and KF analysis may show whether excipients possess the desired polymorphic state and whether significant amounts of amorphous components are present. Together, these studies will ensure lotto-lot consistency in the physical properties that assure flow, compaction, minimal segregation, and compunction ability of excipients used in low-dose formulations. 

Humidity ASTM E871 Standard Test Method for Moisture Analysis of Particulate Wood Fuels Banana bunch 25... 

Moisture Analysis and Condensation Control in Building Envelopes, Ed., H.R. Trechsel, ASTM Manual 40, American Society for Testing and Materials, West Conshohocken, PA, USA, 2001. 

Some of these same techniques as well as other standard methods can be used to determine the purity of the protein polymer preparations. PAGE, high performance liquid chromatography (FIPLC), and moisture analysis are used to analyze the entire sample in bulk. The amount of non-product species which are detected can be used to estimate a maximum purity. Specific contaminants such as polysaccharides, triglycerides, nucleic acids, and endotoxin are detected by specific tests. Assays for host cell derived DNA and antigens is performed with specific reagents developed for these agents. 

Specifications and Analytical Methods. Butanediol is specified as 99.5% minimum pure, determined by gas chromatography (gc), sohdifying at 19.6°C minimum. Moisture is 0.04% maximum, determined by Kad-Fischer analysis (dkecdy or of a toluene a2eotrope). The color is APHA 5 maximum, and the Hardy color (polyester test) is APHA 200 maximum. The carbonyl number is 0.5 mg KOH/g maximum the acetal content can also be measured dkecdy by gc. 

Methods for Chemical Analysis of Graphite Test Method for Ash in a Graphite Sample Test Method for Moisture in a Graphite Sample... 

The water (moisture) content can rapidly and accurately be determined in polymers such as PBT, PA6, PA4.6 and PC via coulometric titration, with detection limits of some 20 ppm. Water produced during heating of PET was determined by Karl Fischer titration [536]. The method can be used for determining very small quantities of water (10p,g-15mg). Certified water standards are available. Karl Fischer titrations are not universal. The method is not applicable in the presence of H2S, mercaptans, sulfides or appreciable amounts of hydroperoxides, and to any compound or mixture which partially reacts under the conditions of the test, to produce water [31]. Compounds that consume or release iodine under the analysis conditions interfere with the determination. 

Part—I has three chapters that exclusively deal with General Aspects of pharmaceutical analysis. Chapter 1 focuses on the pharmaceutical chemicals and their respective purity and management. Critical information with regard to description of the finished product, sampling procedures, bioavailability, identification tests, physical constants and miscellaneous characteristics, such as ash values, loss on drying, clarity and color of solution, specific tests, limit tests of metallic and non-metallic impurities, limits of moisture content, volatile and non-volatile matter and lastly residue on ignition have also been dealt with. Each section provides adequate procedural details supported by ample typical examples from the Official Compendia. Chapter 2 embraces the theory and technique of quantitative analysis with specific emphasis on volumetric analysis, volumetric apparatus, their specifications, standardization and utility. It also includes biomedical analytical chemistry, colorimetric assays, theory and assay of biochemicals, such as urea, bilirubin, cholesterol and enzymatic assays, such as alkaline phosphatase, lactate dehydrogenase, salient features of radioimmunoassay and automated methods of chemical analysis. Chapter 3 provides special emphasis on errors in pharmaceutical analysis and their statistical validation. The first aspect is related to errors in pharmaceutical analysis and embodies classification of errors, accuracy, precision and makes... 

Three standard wood fuels have been studied (a) wood chips, (b) wood pellets, and (c) fuel wood. Figure 17 displays the three types of wood fuels. The fuel wood is from softwood, namely pine and spruce. Table 3 shows the wood fuel data. The moisture, ash and elementary analysis is carried out by an accredited laboratory in Sweden according to Swedish test standards (SS). 

Thermal analysis, moisture uptake and dynamic mechanical analysis was also accomplished on cured specimens. Thermal analysis parameters used to study cured specimens are the same as those described earlier to test resins. The moisture uptake in cured specimens was monitored by immersing dogbone shaped specimens in 71 C distilled water until no further weight gain is observed. A dynamic mechanical scan of a torsion bar of cured resin was obtained using the Rheometrics spectrometer with a temperature scan rate of 2°C/minute in nitrogen at a frequency of 1.6Hz. The following sections describe the results obtained from tests run on the two different BCB resin systems. Unless otherwise noted all tests have been run as specified above. 

After taking suitable coal samples for analysis, removing the blockage and filling the cavity with refractory cement, the thlrd burn test was carried out on the same channel. Figure 5 shows time-data plots for this burn. Because much of the moisture had been driven forward by the preceding burn, only a relatively low-BTU product gas was produced but by cyclical Injection of steam and air, heat values could be periodically Increased. 

Experiments using a matrix of four levels of ferulic acid and four levels of moisture stress demonstrated that the combined action was additive under more stressful levels of the individual factors than in the previous tests. Duke et al. (23) tested the germination of lettuce seeds treated with phenolic acids (1 mM) at water potentials (D-mannitol) of 0, -0.2, -0.4, and -0.6 MPa. The combined action of low water potential and exposure to phenolic acids resulted in an additive detriment to germination, and the authors concluded from probit analysis that the mechanism of action from these sources was similar. Whatever their mechanisms, moisture stress and phenolic acids appear to work together in limiting growth of plants. 

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