Despite the importance of the peptide drugs, their productions have been usually performed by unsustainable and time-consuming methods. Conventional peptide production requires repeated amidation and deprotection steps that increase the...

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Characterizing the Gibbs energy of activation and the enthalpy of reactions typically requires repeated sampling. In this study, a new calorimetric reaction-characterization technique was developed for thermokinetic analysis in a flow reactor. The method was used to simultaneously determine the Gibbs energy of activation from the reaction kinetics and the enthalpy of reaction by fitting the thermal model equation to the spatially resolved temperature profile obtained on a flow reactor. This procedure was verified and comparatively assessed with conventional analytical methods using a family of peptide syntheses as model reactions. The thermal model equation closely fitted the acquired temperature profile. The calculated Gibbs energies of activation agreed closely with the values determined from product yield-time trends obtained using several reactants at different temperatures. The calculated reaction enthalpy was similar to the values obtained from quantum chemical calculations. The findings suggest that spatial regression calorimetry can simultaneously extract more reaction characteristics than conventional calorimetry.

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The basic lattice parameters a, b, and c of (NH4)2BeF4, an incommensurate‐ferroelectric crystal, are measured accurately by using an X‐ray dilatometer in the temperature range including the transition point Ti between the paraelectric and the incommensurate phases, and Tc between the incommensurate and the ferroelectric phases, respectively. The b‐parameter along the ferroelectric axis reveals anomalies at both transition points, while the a‐parameter along the axis exhibiting the incommensurate period does only at Ti. The x italicbi lattice strain along the b‐axis induced by the onset of the incommensurate structure, displays a characteristic mode of temperature dependence which has never been found in other incommensurate‐ferroelectric crystals. According to the temperature dependence of the x italicbP strain due to the spontaneous polarization, it is plausible to anticipate that the ferroelectricity of the crystal is caused by some improper ferroelectric origin.