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Hypercalcaemia and leucocytosis are common in our patients with progressive oral squamous cell carcinoma (SCC). However, the precise incidence, prognostic value, and correlation with the condition of the tumour remain obscure. A total of 618 patients with oral SCC who were treated primarily between 2007 and 2012 and had serum calcium concentrations and white blood cell count (WCC) measured postoperatively were included in the study. Primary TNM stage, pathological features, and the presence of locoregional recurrence or distant metastasis after comprehensive surgical treatment were recorded. The incidence of hypercalcaemia was 9.1% and that of leucocytosis 7.2%. Hypercalcaemia correlated significantly with size of primary tumour (T status), nodal involvement (N status), TNM stage, perineural invasion, lymphovascular permeation, and recurrence or metastasis of disease. Leucocytosis, however, correlated only with T status, lymphovascular permeation, and recurrence or metastasis. In multivariate analysis of survival, recurrence, metastasis, hypercalcaemia, and leucocytosis were strong independent prognostic factors. Median survival was low if the patient had hypercalcaemia or leucocytosis (179 (range 3–73) days if the patient had distant metastasis, and 43 (range 3–102) days if the patient had locoregional recurrence). The incidence of hypercalcaemia and leucocytosis was high during the course of the disease, and both conditions have an adverse impact on survival from oral SCC. Periodic evaluation of serum calcium concentrations and WCC should be routine during the postoperative period.

Drop solution calorimetry was used to determine the enthalpy of solution in lead borate for three different materials with the chemical composition Y3Al5O12. Crystalline yttrium aluminum garnet (YAG), a crystalline mixture of 3 YAlO3 (perovskite) plus Al2O3 (α-alumina), and a glass, were all synthesized by containerless melting and cooling. The enthalpies of drop-dissolution per mole of Y3Al5O12 were 472.49 ± 4.19, 440.35 ± 3.59, and 196.02 ± 3.39 kJ/mol, respectively, for the garnet, the crystalline mixture, and the glass. The garnet phase is thermodynamically stable with respect to the corresponding mixture of α-alumina and perovskite confirming that the two phase mixture is metastable. The enthalpy of vitrification of YAG is 276.47 ± 5.40 kJ/mol (13.82 ± 0.27 kJ/g atom). This high value for the enthalpy of vitrification is related to the reluctant glass forming ability of the YAG composition. The heat of fusion of Y3Al2O12 is estimated to be 25.8 kJ/g atom or 516 kJ/mol at its melting point, 2240 K.

An increased heat capacity of a supercooled liquid, compared to its superliquidus melt, has been measured in situ in some glass-forming tellurite systems by differential scanning calorimetry (DSC), complementing earlier work on fluorozirconates. This increased heat capacity confirms that restructuring occurs in the supercooled liquid regime, in good agreement with structural investigations. The thermodynamics of restructuring decrease the free energy of the supercooled liquid, and hence diminish the thermodynamic driving force for crystallization, as evaluated using the classical nucleation approach. Glass formation thus results from a combination of restructuring thermodynamics and kinetics. Thermodynamic aspects of glass formation, in fragile, intermediate and strong systems, are systematized by free energy versus temperature diagrams within the supercooled liquid regime. A common basis for glass formation is revealed, that is, a glass-forming liquid has a tendency to retain its high-temperature liquid structure for some temperature range below the liquidus. Major structural change will not take place until much lower temperatures, and culminates in the glass transition. This viewpoint suggests that glass formation is decisively controlled by physical and chemical properties in the high-temperature liquid.

Heat capacities of fluorozirconates between 25 and 800°C have been determined by differential scanning calorimetry (DSC) and transposed-temperature-drop calorimetry. Heat capacities of glasses are relatively similar, while the heat capacities of melts are more distinct among different compositions in the superliquidus range. The average heat capacity between the glass transition temperature ( T g ) and the liquidus temperature ( T l ) has a value close to the heat capacity of the supercooled liquid just above T g , but is higher than the heat capacity of high-temperature melts. Therefore, the fluorozirconate exhibits an increased heat capacity in the T g - T l interval. The region of high heat capacity is related to the restructuring in the supercooled liquid regime. This behavior supports our previous study which suggests a substantial structural change from melt to glass. The restructuring gives excess contributions to heat capacity, enthalpy, and entropy and allows the supercooled liquid to significantly lower its free energy (relative to one which does not change structural state), resulting in a diminished thermodynamic driving force for crystallization. Glass formation in fluorozirconates is not only controlled by kinetics but also assisted by restructuring thermodynamics.

Using high temperature calorimetric techniques, enthalpies of mixing of melts, enthalpies of formation of glasses and enthalpies of formation of crystals have been measured in binary systems ZrF4-BaF2, ZrF4-NaF, ZrF4-LaF3 and selected compositions in the system ZrF4-BaF2-LaF3-AlF3-NaF. The system ZrF4-LaF3 shows essentially zero enthalpies of mixing of melts. In the other systems, there are strongly exothermic enthalpies of mixing. In the binary systems ZrF4-BaF2 and ZrF4-NaF, the enthalpy of mixing of melts and the enthalpy of formation of crystals show minima at the same compositions, Ba2ZrF8 and Na3ZrF7, respectively, indicating the stoichiometric complexes ZrF84− and ZrF73−. These results are discussed in relation to energetics, structure, speciation and acid-base chemistry and suggest the following: ZrF4, LaF3 and AlF3 are anionic complex-formers, while BaF2 and NaF are ionized in the molten state. The coordination number of the zirconium fluoride anionic complex varies with the amount of alkali or alkaline earth fluoride. A model is proposed in which glass-forming melts are dominated by ZrF5− species and lie near deep eutectics. Therefore, glass formation in fluorozirconates involves a substantial structural change, which is dominated by short-range atomic arrangements, from the melt with predominantly ZrF5− to the glass where zirconium is 7 or 8 coordinated by fluorine.

Enthalpies of formation were measured for KGdF 4 , K 2 GdF 5 and KGd 2 F 7 using the transposed temperature drop calorimetry method. These compounds were synthesized by conventional solid state reaction methods using mixtures of KF and GdF 3 . The measured enthalpies of formation from fluorides for KGdF 4 , K 2 GdF 5 and KGd 2 F 7 were − 22.3, − 16.1 and − 18.3 kJ mol −1 , respectively. From these measurements, enthalpies of formation from the elements were computed to be − 2290.0, − 2852.4 and − 3985.2 kJ mol −1 for the respective compounds. These enthalpies were compared with estimated values calculated by two methods previously reported to be effective for multicomponent oxides. Estimated values compare favorably with measured data, with deviations ranging from 0.5 to 2.9%. The errors of 0.5–2.9% correspond to a 16–85 kJ mol −1 uncertainty range for Δ f H 0 of ternary fluorides from binary fluorides. One of these methods, based on the summation of Δ f H 0 values for the constituent binary fluorides, is recommended for the KGdF compounds.