Differential scanning calorimetry method

The structures of two polymorphs of pleconaril, enantiotropically related with a transition temperature of 35.7°C, have been reported [36], Form I was described as consisting of a network of dimers, while Form III was described as a three-dimensional network of monomers. The two forms contradicted the density rule, and the solid solid transition could occur only through a destructive-reconstructive mechanism. A quantitative differential scanning calorimetry method was also described that enabled the quantitative determination of Form I in bulk Form III to be made at levels as low as 0.1%. 

Spink CH. Differential scanning calorimetry. Methods Cell Biol. 2008 84 115-141. 

Chrzanowski FA, Ulissi LA, Fegely BJ, Newman AC. Preformulation excipient compatibility testing, application of a differential scanning calorimetry method versus a wet granulation simulating isothermal stress method. Drug Dev Ind Pharm 1986 12 783-800. 

DIFFERENTIAL SCANNING CALORIMETRY METHODS IN THE DETERMINATION OF THERMAL PROPERTIES OF EXPLOSIVES. 

DDM = Diamino diphenyl methane For the mixtures of epoxy monomers, 1 1 mol ratio was used. Stoichiometric amounts were used in all cases. From differential scanning calorimetry method measurements (10 °C/min). Maximum of the loss modulus from dynamic mechanical thermal analysis measurements. a relaxation peak of the loss factor. Reproduced with permission from M. Sponton, L.A. Mercado, J.C. Ronda, M. Galia and V. Cadiz, Polymer Degradation and Stability, 2008, 93, 2025. 2008, Elsevier [22] ... 

Sonication is also another method of generating co-crystals. It is applied to a solution or suspension. Although this technique is little used in co-crystal screening, a recent study has shown that pure co-crystals could be obtained using ultrasound assisted solution co-crystallization, where conventional solution crystallization failed. he use of melt crystallization methods have also been reported as efficient co-crystal screening methodologies. These techniques include thermal microscopy" " and differential scanning calorimetry methods." ... 

Holdgate, G.A. (2010) Isothermal titration calorimetry and differential scanning calorimetry. Methods in Molecular Biology, 572,101 133. 

The method oxidation induction time (OIT) - ISO 113557-6 of the test specimens/samples was determined by differential scanning calorimetry method (DSC) with Pyris 6 DSK thermal analysis instrument from PerkinElmer, USA, at 210°C and oxygen flow of 20 ml/min. 

Heat conduction differential scanning calorimetry methods for the measurement of metabolic heat rates of plant tissues as a continuous function of temperature were developed by Hansen and Criddle [19]. Thermally induced transitions and heat rates can be determined simultaneously. 

Glass-transition temperatures are commonly determined by differential scanning calorimetry or dynamic mechanical analysis. Many reported values have been measured by dilatometric methods however, methods based on the torsional pendulum, strain gauge, and refractivity also give results which are ia good agreement. Vicat temperature and britde poiat yield only approximate transition temperature values but are useful because of the simplicity of measurement. The reported T values for a large number of polymers may be found ia References 5, 6, 12, and 13. 

In order to optimize each embedding material property, complete cure of the material is essential. Various analytical methods are used to determine the complete cure of each material. Differential scanning calorimetry, Fourier transform-iafrared (ftir), and microdielectrometry provide quantitative curing processiag of each material. Their methods are described below. 

The procedures of measuring changes in some physical or mechanical property as a sample is heated, or alternatively as it is held at constant temperature, constitute the family of thermoanalytical methods of characterisation. A partial list of these procedures is differential thermal analysis, differential scanning calorimetry, dilatometry, thermogravimetry. A detailed overview of these and several related techniques is by Gallagher (1992). 

Difl erential thermal analysis (DTA) and differential scanning calorimetry (DSC) are the other mainline thermal techniques. These are methods to identify temperatures at which specific heat changes suddenly or a latent heat is evolved or absorbed by the specimen. DTA is an early technique, invented by Le Chatelier in France in 1887 and improved at the turn of the century by Roberts-Austen (Section 4.2.2). A... 

The solid-liquid transition temperatures of ionic liquids can (ideally) be below ambient and as low as -100 °C. The most efficient method for measuring the transition temperatures is differential scanning calorimetry (DSC). Other methods that have been used include cold-stage polarizing microscopy, NMR, and X-ray scattering. 

The SCB distribution (SCBD) has been extensively studied by fractionation based on compositional difference as well as molecular size. The analysis by cross fractionation, which involves stepwise separation of the molecules on the basis of composition and molecular size, has provided information of inter- and intramolecular SCBD in much detail. The temperature-rising elution fractionation (TREE) method, which separates polymer molecules according to their composition, has been used for HP LDPE it has been found that SCB composition is more or less uniform [24,25]. It can be observed from the appearance of only one melt endotherm peak in the analysis by differential scanning calorimetry (DSC) (Fig. 1) [26]. Wild et al. [27] reported that HP LDPE prepared by tubular reactor exhibits broader SCBD than that prepared by an autoclave reactor. The SCBD can also be varied by changing the polymerization conditions. From the cross fractionation of commercial HP LDPE samples, it has been found that low-MW species generally have more SCBs [13,24]. 

Many papers deal with the crystallization of polymer melts and solutions under the conditions of molecular orientation achieved by the methods described above. Various physical methods have been used in these investigations electron microscopy, X-ray diffraction, birefringence, differential scanning calorimetry, etc. As a result, the properties of these systems have been described in detail and definite conclusions concerning their structure have been drawn (e.g.4 13 19,39,52)). 

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