Thermogram sodium

A drastically diflEerent reaction is indicated on the thermogram of sodium pentachlorophenate (Figure 3) as a strongly exothermic reaction at 360°C. Upon cooling, essentially pure octachloro-p-dibenzodioxin crystallized. 

Figure 7. Differential thermogram of sodium 2-(2,4-dichlorophenoxy)-5-chloro-...

Fig. 2. Differential scanning calorimetry thermogram of sodium valproate.

Fig. 17 Application of the method of standard additions to the quantitation of free phenol in sodium phenolate. Thermograms are shown for (a) the initial sample, (b) the sample with 1 mg free phenol added, (c) the sample with 3 mg free phenol added, and (d) the sample with 5 mg free phenol added.

Differential thermal analysis (DTA) thermograms of ( )-etodolac sodium salt exhibited endothermic transitions around 80,120, and 297°C and an exothermic transition around 83°C [12]. The exothermic phase change was observed after exposure of the sample to moisture, indicating conversion of the amorphous form of ( )-etodolac sodium salt to a crystalline phase. In contrast, the thermogram of (+)-etodolac sodium salt, after exposure to moisture, showed endotherms at 60, 80, 120, and 297°C, indicating that the salt contained methanol, acetonitrile, and water. There was no sign of degradation product formation. 

TG analysis of pantoprazole sodium was conducted obtained using a TA Instruments model 951 thermogravimetric analyzer system, calibrated using indium. The thermograms were carried out at a heating rate of 10°C/min, the sample size used ranged 5 to 10 mg, and the samples were heated over a temperature range of 50°C to 400°C. 

The TG thermogram shown in Figure 4 for pantoprazole sodium shows a mass loss due to evolution of water equal to 3.1% at temperatures above the onset temperature of pantoprazole sodium (131 °C). At higher temperatures, the compound starts to decompose, reaching about a 40% mass loss at temperature above 300°C. 

Figure 8. DSC thermograms of lignin hydroxymethylated under different sodium to lignin ratios a) 1.0, b) 0.75, c) 0.5, and d) 0.25.

Figure 12 Thermogram of cefazolin sodium showing crystallization (BCDE), product (BHE), and baseline correction for crystallization (CE) [17],...

Figures 11-14 to 11-17 show the differential scanning calorimetry (DSC) thermograph of the acetone/ water solvent mixture with and without the presence of imipenem. The DSC curves indicate endothermic peaks which correspond to the phase transitions. The peaks around O C and —95°C represent the melting of the solid water and acetone phases, respectively. The peaks around — 19°C represent the melting of the solid clathrate phase (Rosso et al. 1975). The clathrate is a solid phase complex of 17 water molecules surrounding a single molecule of acetone, niLDOCllOrCO. In addition, the DSC thermograms indicate only slight temperature flucUiations for the endotherms with the addition of imipenem and the sodium bicarbonate. Therefore, the acetone/water binary phase behavior is not affected significantly by the addition of imipenem and sodium bicarbonate.

DSC thermograms obtained during thawing of starch pastes (sucrose not included) (a) without hydrocolloid, (b) with xanthan gum, (c) with guar gum, and (d) with sodium alginate. Upper curves not-annealed samples numbers indicate Tg onset. Lower curves samples annealed at - 4.5°C numbers indicate onset. Curves were not normalized and correspond to different mass samples. 

Fig. 4. Thermograms of aged ferric oxide gel precipitated with sodium hydroxide. Age of gels given in days.

The thermal analysis (5) of dioctyl sodium sulfo-succinate was conducted on a Du Pont Model 900 themal analyzer in a nitrogen atmosphere. At heating rates of 10 C/ minute and 3°C/minute, the thermogram (Figure 3) shows no endotherm, but an irregular curve after 120°C. No transition was observed except foaming of the sample. 

FIGURE 5. Differential Scanning Calorimetry thermogram of Dioctyl Sodium Sulfosuccinate... 

Thermograms were collected for samples containing SO pg/mL protein at pH S.O in 20 mM sodium acetate with 100 mM NaCl. Calorimeter scan rate was 60 C/h. 

Figure 9 TG data processor displaying thermogram of sodium tartrate dihydrate standard. 

Decomposition is generally observed as a broad exothermic peak. However, variations in experimental conditions can alter the nature of the decomposition. In any case, the decomposition is easily determined by visually inspecting the sample after analysis. Repetition of DSC mns in a sample that has decomposed gives different thermograms than those obtained before the decomposition temperature was reached. In the case of anhydrous sodium dioctylphosphinate, the hydrocarbon melting peak at 56°C was not detected in a second run after the decomposition temperature (77°C) had been reached [55],... 

Figure 8 shows the cooling and the heating thermograms of another W/O emulsion (emulsion 2) constituted of Exxol D80 and Berol 26 (nonionic surfactant) as the oil-continuous phase and a dispersed aqueous solution of 5% (w/w) sodium chloride. 

Figure 10 presents the cooling and heating thermograms of a W/OAV multiple emulsion. The internal phase is constituted of water dispersed in vaselin oil stabilized by lanolin as lipophilic emulsifier. This primary emulsion is then dispersed in water stabilized by sodium lauryl sulfate as hydrophilic surfactant. The droplets dispersed in the oil drops crystallize at -42°C, and the external water phase solidifies at - 17°C. There is no measurable delay in the melting of the solidified droplets. Hence, all droplets of both aqueous phases melt at the same temperature, around 0°C. The shape of the thermogram is similar to that of the melting of a pure compound mentioned in Section II. 

Fig. 5. Calorimetric thermogram for the titration of 23 iM wt GSTPl-1 with 5 gL injections (1 qL first injection) of 2.1 mM EA in 20 mM sodium phosphate, 5 mM NaCl and 0.1 mM EDTA at pH 7.0 and 25°C. Inset plot Comparison between a peak from a calorimetric thermogram for the titration of wt enzyme with EA, reflecting the slow kinetic process caused by covalent modification (solid line) and a representative calorimetric trace of a typical binding peak in the absence of a kinetic process (dashed line).

The time constant t of the heat leak of the system was 1.37 x 10" sec" Typical thermograms of the swelling reaction in water and the deswelling reaction in 1.283 mol sodium chloride solution at 25°C are shown in Fig. 4. 

Klapotke et al. described the energetic properties of sodium 5-trifluoromethyltetrazo-late, sodium 5-pentafluoroethyltetrazolate, and sodium 5-heptafluoropropyltetrazoIate [185]. Based on DSC-thermograms the authors concluded that the 5-perfluoroalkyl-tetrazole salts are thermally and thermodynamically stable energy-rich substances. It was also indicated that the sodium salts of 5-perfluoroalkyltetrazoles showed... 

Figure 16. Thermograms of some gas producing agents (1) graphite (2) sawdust (3) fly ash (4) sodium carbonate...

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