The specific heat capacity of NaBO 2 (aq) solution was determined using a Calvet-type calorimeter at a temperature from 288.15 to 338.15 K and at a concentration from about 0.25 mol•kg −1 H 2 O to near room temperature solubility limit. Combining these specific heat capacity data and thermodynamic and solid−liquid equilibrium data reported in the literature, a temperature-dependent thermodynamic model was developed for the NaBO 2 + H 2 O system based on Pitzer−Simonson−Clegg activity coefficient equations. The model represents all of the properties over a wide temperature and concentration ranges. Combining the binary models of NaCl + H 2 O and Na 2 SO 4 + H 2 O systems published in the previous studies of our group, multitemperature thermodynamic models of the NaBO 2 + NaCl + H 2 O and NaBO 2 + Na 2 SO 4 + H 2 O systems were constructed. These ternary models reproduce the experimental solubility isotherms reported in the literature in general, but some significant inconsistency is still present. More accurate solubility data for these ternary systems at various temperatures are urgent.

The flexure joints are proposed to replace the rigid assembly between the cross-arm and the moving carriages of dual-drive H-type gantry (DHG), for higher reliability and fine rotational alignments. In prior literature, the flexure joint of the DHG is modeled as an ideal linear torsional spring, resulting in inaccurate estimation of the cross-arm's angle. In this work, a generalized analytical kinetostatic model of flexure-linked DHG is built by considering the geometric nonlinearities. The expressions of beam coefficients in the model are obtained from either beam constraint model (BCM) or Timoshenko BCM (TBCM), according to the given criterion of length-to-thickness ratio. The model is capable to accurately estimate any two variables among the rotation angle of the cross-arm, the misalignment of two carriages, and the net driving force, as long as the other is known. Simulations and experiments on the testbed validate the accuracy and show practical appeals of the proposed model.

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