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The standard molar heat capacity measurements on compounds Rb2TeO3 (s), Rb2Te2O5 (s) and Rb2Te4O9 (s) in the Rb–Te(IV)–O system were taken using differential scanning calorimeter in the temperature range 325–675 K. The compounds were synthesized by solid-state route and characterized using X-ray diffraction technique. The molar heat capacity values were least squares analyzed, and the dependence of the molar heat capacity with temperature can be given as, $$ \begin{aligned} C^{\text{o}}_{\text{p,m}} \left( {{\text{Rb}}_{2} {\text{TeO}}_{3} , \, s,T} \right) \, /{\text{J K}}^{ - 1} {\text{mol}}^{ - 1} & = 156.00 + 0.02 \, \left( {T/{\text{ K}}} \right){-}4.12 \times 10^{6} \left( {T \, /{\text{K}}} \right)^{ - 2} \\ C^{\text{o}}_{\text{p,m}} \left( {{\text{Rb}}_{2} {\text{Te}}_{2} {\text{O}}_{5} , \, s,T} \right) \, /{\text{J K}}^{ - 1} {\text{mol}}^{ - 1} &= 216.50 + 0.03 \, \left( {T/{\text{ K}}} \right){-}2.52 \times 10^{6} \left( {T \, /{\text{K}}} \right)^{ - 2} \\ C^{\text{o}}_{\text{p,m}} \left( {{\text{Rb}}_{2} {\text{Te}}_{4} {\text{O}}_{9} , \, s,T} \right) \, /{\text{J K}}^{ - 1} {\text{mol}}^{ - 1} &= 351.80 + 0.04 \, \left( {T/{\text{ K}}} \right){-}3.52 \times 10^{6} \left( {T \, /{\text{K}}} \right)^{ - 2} \\ \end{aligned} $$ From these data, thermodynamic functions such as enthalpy increment (H T o − H 298.15 o ), entropy (S T o ) and Gibbs energy functions (fef) were evaluated.

Rb2CeO3 compound was prepared by conventional solid-state reaction route. The Gibbs energy formation of the compound was determined by measuring the partial pressure of CO2 over the equilibrium phase mixture {Rb2CO3(s) + CeO2(s) + Rb2CeO3(s)} using Knudsen effusion quadrupole mass spectrometry. Gibbs energy formation of the compound, $$\Delta_{\text{f}} G_{\text{m}}^{o}$$ , as a function of temperature is obtained as: $$\Delta_{\text{f}} G_{\text{m}}^{\rm o} \left( {{\text{Rb}}_{2} {\text{CeO}}_{3} ,{\text{s}},T} \right)({\text{kJ}}\;{\text{mol}}^{ - 1} ) \, \left( { \pm 7} \right)\; = \; - 1601 + 0.41 \times \left( {T/K} \right)(991 \le T/K \le 1124)$$ The molar heat capacity of the compound, $$C^{\text o}_{\text{p,m}}$$ , was measured from 390 to 1100 K using a differential scanning calorimeter and is given as: $$C^{\rm o}_{\text{p,m}} \left( {{\text{Rb}}_{2} {\text{CeO}}_{3} ,{\text{s}},T} \right) \, ({\text{J}}\;{\text{mol}}^{ - 1} \;{\text{K}}^{ - 1} ) = 210.8 + 0.0061 \times \left( {T/K} \right){-}6348435/\left( {T/K} \right)^{2}$$ Based on these experimental data, thermodynamic table of the compound was also generated from 298.15 to 1000 K. Standard molar enthalpy of formation $$\Delta_{\text{f}} H_{\text{m}}^{\rm o}$$ (298.15 K) and standard molar entropy $$S_{\text{m}}^{\text o}$$ (298.15 K) of Rb2CeO3 are −1643 kJ mol−1 and 61.5 J K−1 mol−1, respectively.

The Li2TeO3 (s) and Li2TeO4 (s) were synthesized using solid-state reaction route and characterized using X-ray powder diffraction techniques. Molar heat capacity measurement on Li2TeO3 (s) and Li2TeO4 (s) were carried out using differential scanning calorimeter. The molar heat capacity values were least squares analyzed, and the dependence of molar heat capacity with temperature for Li2TeO3 (s) and Li2TeO4 (s) can be given as, $$\begin{aligned} C^{\text{o}}_{\text{p,m}} \left( T \right)\left( {{\text{Li}}_{ 2} {\text{TeO}}_{ 3} , {\text{ s}},\;T} \right) \, /{\text{J K}}^{ - 1} {\text{mol}}^{ - 1} = \, 107.56 \, + \, 0.05\;T\left( {\text{K}} \right) \, {-} \, 2.21 \, \times \, 10^{6} \;T^{ - 2} \left( {\text{K}} \right) \left( {325 \, \le \;T\left( {\text{K}} \right) \, \le \, 675} \right). \hfill \\ C^{\text{o}}_{\text{p,m}} \left( T \right)\left( {{\text{Li}}_{ 2} {\text{TeO}}_{ 4} , {\text{ s,}}T} \right) \, /{\text{J K}}^{ - 1} {\text{mol}}^{ - 1} = 121.59 \, + \, 0.06\;T\left( {\text{K}} \right) \, {-} \, 1.92 \, \times \, 10^{6} \;T^{ - 2} \left( {\text{K}} \right) \left( {325 \, \le \;T\left( {\text{K}} \right) \, \le \, 675} \right). \hfill \\ \end{aligned}$$ From these data, other thermodynamic functions such as enthalpy increment ( $$H^{\text{o}}_{\text{T}} - H^{\text{o}}_{298.15}$$ ), entropy ( $$S^{\text{o}}_{\text{T}}$$ ) and Gibbs energy functions {−( $$G^{\text{o}}_{\text{T}} - H^{\text{o}}_{298.15}$$ ) T −1} were computed.

The enthalpies of formations of Ce2(MoO4)3(s) and Sm2(MoO4)3(s) have been measured at 298.15 K using semi adiabatic solution calorimetry. The precipitation reaction between RE(NO3)3·6H2O(s) (R= Ce, Sm) and ammonical solution of Na2MoO4(s) was studied. From the enthalpy of precipitation and other required auxiliary data, $$ \Updelta_{\text{f}} H_{\text{m}}^{ \circ } \left( { 2 9 8. 1 5 {\text{ K}}} \right) $$ of Ce2(MoO4)3(s) and Sm2(MoO4)3(s) have been calculated for the first time as −4388.7 ± 3.6 and −4363.4 ± 4.1 kJ mol−1, respectively. The enthalpy of hydration of anhydrous Ce(NO3)3(s) to Ce(NO3)3·6H2O(s) has been calculated. $$ \Updelta_{\text{f}} H_{\text{m}}^{ \circ } \left( {{\text{MoO4}}^{ 2- } ,\,{\text{aq}},\, 2 9 8. 1 5 \,{\text{K}}} \right) $$ has also been measured and calculated as −995.1 kJ mol−1 from required literature data.

Eleven cases of thyroid cancer occurring in patients below 15 years of age are presented. The youngest patient was 4 years old. There were 4 boys and 7 girls in the study group. None of the patients had received head and neck irradiation. All patients had well differentiated cancers; there were 4 follicular carcinomas and 3 of these occurred in patients below 10 years of age. Six patients presented with solitary thyroid nodules. Lymph node involvement had occurred in 63.7% of cases. One patient presented with CNS metastasis. Treatment aimed at near total thyroidectomy was performed in 9 patients. Two patients died of the disease during the follow up period and another 3 patients are alive. Postoperatively radioactive iodine was routinely used for evaluating and treating residual and recurrent disease.

Zum Verstanduis des Dauerverhaltens eines Stoftes wie Holz ware es nutzlich, Daten von Holzarten mit moglichst verschiedener Rohdichte zu sammeln und diese mit jenen Eigenschaften zu korrelieren, die fur das elastisch-plastische und orthotrope Verhalten von Holz bestimmend sind. Die vorliegenden Untersuchungen haben gezeigt, das der Faserrichtungswinkel und das aufgebrachte Biegemoment erheblichen Einflus auf die Dauerfestigkeits-Eigenschaften haben. Daraus kann geschlossen werden, das die Verwendung von Holz mit hoherem Faserrichtungswinkel dort zu vermeiden ist, wo schwingende Belastungen zu erwarten sind, und das ein Winkel von hochstens to als angemessene Sicherheitsgrenze bei der Materialauswahl fur Falle mit schwingender Belastung gelten kann.

In conclusion, it may be stated that in order to understand a complete fatigue behaviour of a material like timber it would be useful to obtain more information on these lines for other timbers of varying densities, differing moisture content, and other varying initial conditions and to correlate these with other properties which depend on the elasto-plastic and orthotropic behaviour of wood. The present investigations have, however, indicated the general trend of mechanical deterioration with increasing reversals in torsion as well as in bending; but the number of reversals required under torsion are far less compared to those in bending.